Signaling and regulation of G protein-coupled receptors in airway smooth muscle
© The Author(s) 2003
Received: 14 August 2002
Accepted: 14 October 2002
Published: 14 March 2003
Signaling through G protein-coupled receptors (GPCRs) mediates numerous airway smooth muscle (ASM) functions including contraction, growth, and "synthetic" functions that orchestrate airway inflammation and promote remodeling of airway architecture. In this review we provide a comprehensive overview of the GPCRs that have been identified in ASM cells, and discuss the extent to which signaling via these GPCRs has been characterized and linked to distinct ASM functions. In addition, we examine the role of GPCR signaling and its regulation in asthma and asthma treatment, and suggest an integrative model whereby an imbalance of GPCR-derived signals in ASM cells contributes to the asthmatic state.
G protein coupled receptors (GPCRs) comprise a superfamily of proteins capable of transducing a wide range of extracellular signals across the plasma membrane of the cell into discrete intracellular messages capable of regulating numerous, diverse cell functions. Over 800 GPCRs have been cloned to date and over 1000 are suspected in the human genome . The majority of all prescribed drugs target either activation of GPCRs or their downstream signals. This holds true for drugs used in the management of airway diseases such as asthma; it is generally accepted that GPCRs on airway smooth muscle (ASM) are the direct targets of the majority of anti-asthma drugs.
Until recently most research efforts examining GPCR expression, function, and regulation in ASM have focused on those receptors capable of dynamic regulation of ASM contractile state and consequently, airway resistance. However, the growing appreciation of ASM as a pleiotropic cell capable of regulating airway resistance via "synthetic functions" has provided a much wider context in which to consider the relevance of numerous ASM GPCRs. GPCRs whose activation has little or no direct impact on contractile state may instead modulate ASM growth or the secretion of various cytokines, chemokines, eicosanoids, or growth factors that orchestrate airway inflammation through actions on both mesenchymal and infiltrating cells. These effects may ultimately influence airway resistance by: 1) promoting airway remodeling that impacts the mechanics of ASM contraction in vivo; or 2) regulating the inflammatory response to either disrupt the balance of local pro-contractile/relaxant molecules or alter electro- or pharmaco-mechanical coupling in ASM. Accordingly, it is no longer permissible to judge the relevance of a given ASM GPCR based on its ability to dynamically modulate ASM contractile state and airway resistance. Indeed, our newfound appreciation of multiple experimental endpoints defining ASM function has aided efforts to identify relevant ASM GPCRs and their signaling properties.
In this review we will summarize the signaling and functional effects of various GPCRs that have been identified in ASM cells. In addition, we will consider how the regulation (or dysregulation) of GPCR signaling potentially impacts asthma pathogenesis and treatment.
Models for analyzing GPCR signaling in ASM
Models for analyzing GPCR signaling in ASM run the spectrum of integrative to reductionist approaches, each having certain advantages and disadvantages. Integrative in vivo models in which GPCR ligands are administered systemically or through inhalation can suggest the presence of ASM GPCRs capable of mediating bronchoconstrictive or relaxant effects. Such experiments can provide important insight into the role of a given GPCR in regulating lung resistance, and suggest the utility of targeting a receptor in order to control bronchospasm. However, the direct target cell of delivered agents is often unclear, and frequently the response of ASM is secondary to actions on other cell types. For example, inhaled agents can provoke the release of bronchoreactive substances from multiple cell types that in turn engage ASM GPCRs, or regulate autonomic control of ASM contraction through actions on pre- or post-ganglionic neurons or reflex arcs [2–4].
A more controlled environment in which to characterize ASM GPCRs is provided by ex vivo analyses of tracheal or bronchial smooth muscle isolated as strips or as part of a complex including cartilaginous ring. This approach reduces, but does not eliminate, neural or paracrine effects on ASM that can dominate functional ASM responses in vivo. Such effects can persist because preparations still include autonomic effector and sensory nerve fiber endings, epithelium, fibroblasts, and blood cells capable of releasing constricting/relaxing agents in response to exogenous agents or, possibly, mechanical forces . Consequently, intelligent design of such ex vivo analyses can help clarify the in vivo effects of numerous agents and identify their target cells. For example, immunohistochemical analysis and tissue bath mechanics of excised ASM strips suggest that the pronounced bronchoconstriction elicited by inhaled adenosine or adenosine monophosphate in asthmatic subjects or sensitized animals can be attributed primarily to histamine release from mast cells in close proximity to or imbedded in ASM tissue [6–11].
Arguably, the development of ASM cell cultures has provided the most reliable system for identifying and characterizing ASM GPCRs. Typically generated by enzymatic dissociation of ASM cells from sections of tracheae or bronchi, ASM cultures provide a pure population of ASM cells that can be greatly expanded, and thus are amenable to extensive pharmacological, biochemical, and molecular analyses not possible in vivo or with tissues [12, 13]. Cells of ASM cultures of several species (including human, canine, bovine, guinea pig, and mouse) have been shown to be morphologically and functionally similar to ASM in vivo; they stain for smooth muscle-alpha-actin and myosin heavy chain, and exhibit signaling and functional responses that are consistent with ASM function observed or suspected in vivo [12–15].
The power of ASM cultures as an experimental model capable of verifying existing and identifying new signaling paradigms, while also establishing their physiologic relevance, is under-appreciated. This power is largely attributed to the fact that ASM cells possess physiologic levels of most signaling components (e.g., receptors, effectors, and downstream signaling intermediates), yet many signaling pathways are readily characterized with robust signal to noise ratios. Most importantly, numerous ASM cell functions (including growth, synthesis/secretion of autocrine/paracrine factors, and to a limited extent, contraction) are also easily quantified and can be linked to their associated signaling events. In many other cell culture systems such linkage of signaling to relevant cell function cannot be achieved. For example, the majority of studies revealing novel receptor-mediated signaling paradigms have utilized expression systems such as COS or HEK293 cells to express recombinant receptors or signaling components in order to delineate pathway interactions and their modes of regulation. It is unclear whether such paradigms occur under relevant conditions in which most signaling components are expressed at low levels and their actions may be constrained by compartmentalization [16, 17]. Moreover, whether such signaling has any relevance to cell function is unclear, because such cells typically either lack discrete measurable functions or their functions are known to be dysregulated (e.g., physiologic regulation of growth cannot be studied in a transformed cell). Recent studies [18–20] have begun testing the applicability and physiologic relevance of various GPCR signaling paradigms in cultured ASM cells.
However, ASM cultures as a model system are far from perfect. That ASM cells in culture lack the context of the in vivo condition is not only a strength but also an inherent limitation of this reductionist model. Moreover, like most primary cells grown in culture, ASM cells undergo a degree of de-differentiation that coincides with a loss or increase in various signaling elements and functional apparatus . Specific changes in ASM cells relevant to GPCR signaling that are known to occur in culture include a rapid and progressive decrease in the expression of Gq-coupled receptors such as the m3 muscarinic acetylcholine receptor (m3 mAChR)  and the cysteinyl leukotriene type 1 receptor (CLT1R; Stuart Hirst, personal communication). In addition, contractile function of cultured ASM cells is rapidly diminished, coinciding with reduced expression of smooth muscle alpha-actin and myosin heavy chain, calponin, h-caldesmon, beta-tropomyosin, and myosin light chain kinase (MLCK) . However, Shore, Fredberg, and colleagues have developed a model for examining agonist-induced changes in stiffness of cultured ASM cells that has provided useful information linking regulation of GPCR signaling with ASM contractile state . Interestingly, Stephens , Halayko, Solway [25–27], and colleagues have demonstrated that prolonged serum starvation of cultured canine ASM cells can beget a subpopulation of cells that reacquire high m3 mAChR and contractile/cytoskeletal protein expression and thus contractile function. These findings suggest a potentially powerful strategy for delineating elements critical to Gq-coupled receptor signaling and pharmaco-mechanical coupling in ASM.
Functions in ASM1
5-HT2c identified, other subtypes likely
Low levels suggested in human ASM
Mediates effects of autocrine and paracrine adenosine
Only response in lung or ex vivo occurs with βAR antagonist present
RLXN, Cyt, GI
Robust activation of PLC and PLA2 in cultured ASM;putative B3 yet to be cloned
CLT1R antagonists most therapeutic of all GqCR antagonists
Gq, Gi, G12/13
Most subtypes exhibit promiscuity toward G proteins
RLXN, GI, Cyt
Indirect evidence for expression of EP1, EP3, and EP4
Exhibits homologous and heterologous desensitization
Responsive to autocrine PGI2 induced by cytokines via COX-2 induction
Mediator of acute adenylyl cyclase inhibition, chronic sensitization
Rapid reduction of expression in culture
Gq, Gi, G12/13
Thrombin most mitogenic GPCR agonist; subtype promiscuity towards G proteins
P1 may also be expressed
Gq, Gi, G12/13 (?)
Coupling specificity poorly characterized in ASM
However, as noted above ASM cells do more than contract and studies of other functional outcomes in ASM suggest a potentially important role for numerous Gq-coupled receptors in modulating ASM synthetic functions. Both thrombin (capable of activating Gq through protease-activated receptors (PARs) ) and lysophosphatidic acid (LPA) (capable of activating Gq through endothelium differentiation gene (EDG) receptors) are strong stimulators of cultured ASM DNA synthesis and cell proliferation. These effects appear in part Gq-dependent (Billington and Penn, unpublished observations) and may be mediated by the capacity of Gq signaling to stimulate the p42/p44 MAPK (via PKC-mediated phosphorylation of Raf-1) and p70S6K pathways and therefore induce promitogenic transcription factor activation, cyclin D1 induction, and upregulate the translational machinery necessary for cell cycle progression [36, 37]. Moreover, numerous Gq-coupled receptor agonists including thrombin, lysophosphatidic acid, leukotriene D4 (LTD4), endothelin, histamine, thromboxane (activating Thromboxane A2 / Prostaglandin (TP) receptors), and sphingosine-1-phosphate (SPP) (activating EDG receptors) have been shown to potentiate the mitogenic effects of receptor tyrosine kinase signaling, although it has not been established that Gq activation per se mediates this effect.
Gq-dependent activation of PKC and p42/p44 also promotes phosphorylation and activation of phospholipase A2 (PLA2), which contributes to rapid eicosanoid synthesis in ASM cells stimulated with bradykinin (acting on B2 bradykinin receptors). Other effects reported to involve Gq activation by ASM GPCRs include actin polymerization induced by LPA, endothelin, or carbachol, which appears to occur via a Rho-dependent mechanism . This suggests that effectors other than PLC can be directly activated by Gq in ASM.
Whereas Gq-coupled receptors are the principal mediators of ASM contraction, Gs-coupled receptors on ASM play a central role in promoting relaxation of contracted ASM and in conferring prophylactic "bronchoprotection". Inhaled beta-agonists, which activate the Gs-coupled beta-2-adrenergic receptor (β2AR) on ASM, are the most widely used agents in asthma therapy and are universally recognized as the treatment of choice for acute asthma attacks. Several other Gs-coupled receptors, including the E-Prostanoid 2 (EP2) prostaglandin E2 (PGE2) , IP prostacyclin ( and Pascual and Penn, unpublished observations), A2b adenosine , and vasoactive intestinal peptide (VIP) receptors have been identified in ASM and represent intriguing, albeit elusive, therapeutic targets (Table 1).
Adenylyl cyclase (AC) is the principal effector of Gs-coupled receptor transmembrane signaling. Nine isoforms (type I through IX) of AC are known to exist . RT-PCR has identified transcripts of all AC subtypes except III and VIII in human ASM cultures, although immunoblot analysis suggests the presence of only V/VI (existing antibodies do not distinguish between type V and VI), and analyses of AC regulation in human ASM cultures (discussed below) are consistent with the expression of AC V and VI [46, 47]. Interestingly, AC subtype expression in ASM cultures may be species specific, as regulatory features of AC in bovine, canine, and guinea pig ASM suggest prominent expression of AC II [48–51], whereas a minimal  or no  level of AC II transcripts were detected in human ASM (see below).
Adenylyl cyclase isoforms are subject to multiple forms of regulation (discussed below), although dynamic activation of AC under physiologic conditions occurs almost exclusively by interaction with Gαs . Gαs activation of AC catalyzes ATP to cyclic AMP (cAMP), which in turn binds to the regulatory subunits of the cAMP-dependent protein kinase (protein kinase A or PKA). The cAMP-bound regulatory subunits then dissociate from and thereby activate the catalytic subunits of the enzyme, which in turn phosphorylate and regulate the activity of numerous proteins, including the transcription factor CREB. PKA activity is presumed responsible for the majority of cellular actions elicited by Gs-coupled receptor activation, which in ASM include relaxation, altered transcription of numerous genes that impact airway inflammation and remodeling [53, 54], inhibition of cell growth, and ion channel gating . However, cAMP/PKA -independent signaling by Gs-coupled receptors has also been proposed and may have important functional consequences in ASM. These include beta-agonist-induced actin depolymerization , direct activation of Ca2+-sensitive K+ channels by Gαs subunits , and possibly other ill-defined signaling events that promote relaxation and are unaffected by exposure of ASM to pharmacological inhibitors of PKA .
A role for Gi-coupled receptors in modulating growth in ASM is suggested by studies that demonstrate that pertussis toxin (which ADP-ribosylates and inhibits Gαi) partially inhibits ASM DNA synthesis stimulated by numerous GPCR ligands including carbachol (activating the m2 mAChR), LPA, SPP, endothelin, and thrombin [18, 38]. The mechanism mediating Gi-stimulated growth of ASM is unclear, although actions of both α and βγ subunits may be involved. Gβγ has the potential to stimulate p42/p44 MAPK via activation of PLC and PKC, and can also mediate p42/p44 activation through Src-dependent transactivation of the epidermal growth factor (EGF) receptor . However, none of these mechanisms has been established in ASM. On the contrary, transactivation of the EGF receptor is not induced by thrombin, carbachol, or LPA in human ASM cultures, and increased p42/p44 MAPK signaling does not appear to mediate the synergistic effect of several GPCR agonists on EGF-stimulated ASM growth [18, 19]. These latter findings suggest potentially novel mitogenic signaling events and define cooperativity between GPCRs and receptor tyrosine kinases in mediating ASM growth.
G12/13 coupled receptors
Signaling via activation of the G12/13 family has not been characterized as extensively as has that by other heterotrimeric G proteins. The effector molecules that interact directly with G12 and G13 are not well established, with the exception of members of a family of guanine nucleotide exchange factors for the small G protein Rho . The GPCRs capable of activating G12 or G13 are also unclear. Immunoblot analysis demonstrates Gα12 and Gα13 protein in rat bronchial smooth muscle tissue, and levels are elevated by repeated antigen challenge (see below). In ASM cells, those GPCRs activating G12/13 have not been characterized, although SPP/LPA-activated EDG receptors, thrombin-activated PAR receptors, and TP receptors are candidates. The profound effect of inhibitors of Rho and Rho kinase on GPCR-mediated changes in contractile sensitization [69, 70] and actin polymerization  strongly suggest a physiologic role for G12/13 signaling in ASM.
Regulation of GPCR signaling
Signaling by GPCRs is a highly regulated process. One critical way in which a cell controls its response to extracellular GPCR ligands is through regulation of the expression and activity of each component of the GPCR-G protein-effector pathway. Either a loss (desensitization) or increase (sensitization) in responsiveness of transmembrane signaling components can be evoked to presumably preserve the cell/organism from excessive signals or ensure detection and reaction to infrequent or minimal signals. In ASM, studies of regulation of GPCR signaling have focused on changes that occur in receptor and G protein expression and second messenger generation in cells, or on altered contractile/relaxant effects on ASM in vivo or ex vivo. No studies to date have considered the effect of desensitization or sensitization of GPCR signaling on GPCR-mediated functions in ASM other than contraction.
Regulation at the receptor locus
GPCRs are also subject to phosphorylation and desensitization by PKA and PKC. Accordingly, any agent capable of activating cellular PKA or PKC (e.g., other GPCR agonists, phosphodiesterase inhibitors) can diminish GPCR responsiveness. PKA and PKC-mediated phosphorylation causes a degree of receptor uncoupling from G protein, but it does not promote arrestin binding to receptor and rapid internalization. Such heterologous desensitization of a given GPCR is typically not as profound as homologous desensitization. Cultured ASM cells exposed briefly to either PGE2, adenosine, forskolin (all stimulators of cAMP production and PKA activation) or phorbol ester (a PKC activator) exhibit diminished isoproterenol-stimulated cAMP production [42, 46, 71, 72]. Similarly, chronic exposure of ASM cells to interleukin-1β (IL-1β), tumor necrosis factor alpha (TNF-α), or transforming growth factor beta (TGF-β) also results in heterologous desensitization of the β2AR, presumably via the induction of Cyclo-oxygenase-2 (COX-2) activity and the autocrine effect of induced PGE2 [76–80]. The PGE2- or IL-1β-mediated loss of beta-agonist-stimulated second messenger generation is associated with a loss in the relaxant effect of beta-agonist on carbachol-contracted ASM cells in culture . The H1 histamine receptor exhibits both homologous  and heterologous  desensitization, the former presumably mediated exclusively by GRKs, the latter induced by phorbol ester in a PKC-dependent manner.
Down-regulation, defined as a loss in receptor density, occurs as a result of increased receptor degradation or reduced receptor synthesis. Recovery from GPCR down-regulation is a relatively slow process and requires new receptor synthesis. Virtually all GPCRs studied to date undergo some degree of downregulation when chronically exposed to their agonist. Other agents can promote a loss of GPCR density through either inhibition of receptor gene transcription, or via ill-defined mechanisms that promote receptor degradation.
Arrestin-dependent internalization of GPCRs has been identified as a pathway leading to lysosomal degradation of GPCRs . Recently studies also suggest that β2ARs and CXCR4 receptors are subject to ubiquitination that ultimately directs internalized receptor to lysosomes [83, 84], or in the case of mu and delta opioid receptors, to proteosomal degradation . Chronic exposure of ASM cells to beta-agonist, or ASM tissue to histamine results in down-regulation of the β2AR  and H1 histamine receptor , respectively. The effects of a receptor's agonist and other agents (e.g., glucocortoids, cytokines, beta-agonists) on pre- and post-transcriptional regulation of new receptor synthesis have been characterized for numerous GPCRs in ASM or lung [81, 87–97]. Although receptor degradation probably plays a prominent role in the down-regulation of GPCRs in ASM, the trafficking of GPCRs to their degradation fate has not been studied in ASM cells.
Up-regulation of GPCR expression is also observed for numerous GPCRs in numerous cell types and is an important physiologic means of conferring sensitization of GPCR signaling. Increased GPCR expression, mediated by increased gene transcription as well as post-transcriptional mechanisms, is frequently induced experimentally by chronic treatment of cells with antagonist. Antagonist-mediated up-regulation of GPCRs is relatively unexplored in ASM cells or tissue, although chronic treatment of rabbits with atropine has been shown to up-regulate both m2 and m3 mAChRs in the airway . Transcription regulation of most GPCR genes in ASM cells is poorly understood, but should be greatly abetted by the increasing adroitness in applying molecular techniques to primary ASM cultures and by the emergence of models of ASM phenotype regulation [27, 93].
One final means by which GPCR responsiveness is influenced is by receptor genotype. Single nucleotide polymorphisms (SNPs) that result in changes in β2AR expression, cellular distribution, and signaling have been identified in both the promoter and coding region of the β2AR gene [99, 100]. SNPs identified in the β2AR promoter have been shown to affect receptor expression [101, 102]. Among those polymorphisms detected in the coding region, Arg→Gly16 exhibits enhanced agonist-induced desensitization (of beta-agonist-stimulated cAMP generation) and down-regulation, whereas Gln→Glu27 is decidedly desensitization- and down-regulation-resistant. Importantly, these properties are evident in β2ARs expressed endogenously in ASM cultures . SNPs identified in other GPCRs (including the α2a- , α2b- , and β1-adrenergic receptors [105, 106]) have also been shown to be of functional consequence, although their characterization has been performed primarily in either cell expression models or in the cardiovascular system.
The relevance of β2AR SNPs to asthma and asthma therapy are discussed below.
Regulation at the G protein locus
Regulation of G protein expression and activity has the potential to modify GPCR signaling. Gα subunit GTPase activity is known to be regulated by recently discovered RGS (regulators of G protein signaling) proteins . Experimental manipulation of RGS protein expression can alter GPCR signaling, but the physiologic role of RGS proteins is unclear. Interestingly, GRK2 has been recently shown to contain an RGS domain that can interact specifically with Gαq and quench its activity .
Overexpression of Gα subunits in various cell systems can enhance GPCR signaling, and the expression of certain Gα subtypes is altered in various disease state models (see below). In human ASM cells in culture, overexpression of Gαs increases both basal and Gs-coupled receptor-mediated cAMP production . Whether altered Gα expression or localization impacts GPCR signaling under physiologic conditions is somewhat controversial. Endogenous expression of G proteins is typically much higher than that of GPCRs or effectors, suggesting that most GPCR-G protein-effector signaling is probably limited more by the expression/activity of the effector or GPCR than by that of the G protein . However, a growing appreciation that GPCR signaling may be highly compartmentalized  suggests that even small changes in Gα subtype expression may regulate GPCR signaling. Consistent with this notion are observations that exposure of lung [110–112], ASM strips ex vivo [113, 114], or ASM cultures  to various agents can elicit a loss of β2AR function that is associated with increased expression of specific Gαi isoforms or decreased expression of Gαs.
Regulation at the effector locus
Although the study of endogenously-expressed GPCR effectors lags behind that of GPCRs and heterotrimeric G proteins, the recent cloning of numerous PLC and AC isoforms and their analysis in expression systems has facilitated insight into the tremendous complexity of effector regulation. Multiple mechanisms by which PLC activity is regulated have been demonstrated . PLCβ activity is greatly influenced by substrate availability; the agonist-sensitive pool of PIP2 is metabolized several times per minute , meaning that recycling of products of hydrolysis, and the activity of numerous enzymes involved in this process, is critical to PLC activity. Localization of PLC isoforms to the membrane appears to be regulated by interaction of pleckstrin homology domains in PLC with specific phosphoinositides and Gβγ subunits [117, 118]. PLCβ2 and PLCβ3 isoforms can be phosphorylated by PKA, which results in reduced activity [119–121]. Other PLC isoforms can be phosphorylated by PKC, albeit with no apparent consequence [115, 122]. Interestingly, activated PLCβ isoforms serve as GTPase-activating proteins for Gαq and thus participate in negative feedback control of their activation .
Unfortunately our understanding of PLC regulation is derived largely from studies using cell-free models or cellular expression systems. With the exception of work from Martin and colleagues [124–126] and Pyne and Pyne , few studies to date have examined PLC signaling and its regulation in ASM cells.
Studies of AC regulation have been limited by the extremely low levels of endogenous AC isoform expression, and by the unstable nature of the AC protein, which has rendered its purification and characterization problematic. Detection of endogenous AC protein with currently available antibodies is often difficult in many cell types (including ASM), despite the suggestion of specific isoform expression in parallel analyses of AC mRNA levels. However, expression of recombinant AC isoforms has helped identify some regulatory features of AC [45, 128, 129]. AC I, II, III, V, and VII are subject to phosphorylation by PKC, which results in their sensitization [130–134]. Conversely, phosphorylation of AC V and VI by PKA inhibits AC activity [135–137]. βγ subunits potentiate the stimulatory effect of Gαs subunits on AC II, IV, and VII [138–140]. Calcium/calmodulim is also a physiologic regulator of AC I, III, and VIII; isoforms whose expression tends to be restricted to the brain and olfactory epithelium .
Adenylyl cyclase (as well as other elements and regulators of Gs-coupled receptor signaling) and its activity appear to be concentrated in lipid rafts or caveolae, suggesting that compartmentalization serves to facilitate initiation or quenching of GPCR signaling [141, 142]. Similarly, components of PLC signaling, but not PLC isoforms themselves, are also recovered in caveolin-containing membrane fractions .
In ASM, AC regulation is evident but appears species-specific. Stevens et al.  and Pyne and Pyne [127, 144] demonstrated that bradykinin, platelet-derived growth factor (PDGF), and phorbol ester stimulate cAMP formation in guinea pig ASM, presumably via a PKC-dependent enhancement of AC II activation by Gαs. Chronic treatment of canine ASM cultures with carbachol reduced basal and agonist-stimulated AC activity, an effect that was reversed by PKC inhibition . Similar results were obtained in studies of bovine ASM . In contrast, chronic treatment of human ASM cultures with carbachol (as well as numerous other agonists of Gi-coupled receptors) promoted AC sensitization but in a PKC-insensitive, pertussis-toxin sensitive manner . This manner of AC sensitization has been observed in other cell types including neuronal cells treated chronically with opioids, and appears to be an adaptive response (tolerance) to counteract persistent Gi signaling [64, 145, 146]. In an analysis of heterologously-expressed AC isoforms in COS cells, Nevo et al  determined that chronic Gi activation resulted in sensitization of AC I, V, VI, and VIII, and reduced activity of AC II, IV, and VII. Thus, the profile of AC transcripts and regulatory features of AC in human ASM suggest a predominance of AC VI or V in human ASM, whereas PKC-sensitive isoforms, perhaps AC II, may be preferentially expressed in non-human ASM.
Aberrant GPCR signaling and airway hyperreactivity
Changes in airway structure and ASM contractile state are the principal causes of increased airway resistance in asthma. Altered airway composition and architecture affect airway resistance through mechanisms that are both independent of and complimentary to changes in ASM contractile state. Excessive mucous production and edema are physical impediments to conductance, whereas edema and increased ASM mass alter airway geometry to amplify the effect of ASM contraction on airway lumen diameter [148–154].
Altered GPCR agonist presentation
On one level we can consider the contribution of a disrupted balance of procontractile and prorelaxant stimuli accessible to ASM, whereby 1) an increase in procontractile stimuli in the asthmatic airway promotes greater activation of GPCRs (Gq- and Gi-coupled receptors) mediating contraction, or 2) a reduction in agonist levels serving Gs-coupled receptor activation diminishes prorelaxant signaling. It is well established that numerous GPCR agonists (e.g., acetylcholine, histamine, and thromboxane) capable of evoking ASM contraction are elevated in the airways of many asthmatics [155–159]. The source of these agonists may be neural cells (increased parasympathetic discharge caused by numerous factors) inflammatory cells (e.g., from mast cells, platelets), or possibly resident mesenchymal airway cells (including ASM itself). Exacerbating this condition in asthma is the sloughing of airway epithelium, which constitutes a loss of diffusion barrier and may increase ASM access preferentially to procontractile agonists [152, 160, 161]. These findings strongly suggest that exaggerated procontractile GPCR agonist presentation to ASM occurs with asthma and contributes to increased ASM tone. Less certain is whether the levels of prorelaxant GPCR agonists are suppressed in asthmatics. Such agents (e.g., catecholamines, certain eicosanoids) tend to have short half-lives and their local concentrations are not easily measured. However, it should be recognized that the loss of airway epithelium in asthma also constitutes a loss of relaxant factors that target either GPCRs (e.g. PGE2) or other pathways (nitric oxide) in ASM [152, 162–164].
Altered GPCR responsiveness to agonist
On another level we can consider the contribution of altered GPCR responsiveness to a given level of agonist presented to ASM, such that the sum of GPCR-generated signals results in higher than normal increases in intracellular calcium. Such altered GPCR responsiveness may result from either sensitization of Gq- or Gi-mediated signaling that promotes increased calcium flux, or from desensitization of Gs-coupled receptor signaling that antagonizes signaling leading to elevated calcium. Numerous studies suggest that both of these phenomena occur and contribute to ASM hyperresponsiveness.
Recent findings demonstrate that GPCR-mediated contraction of ASM strips ex vivo is augmented by various "sensitization" strategies . These strategies include sensitization to allergen in vivo [68, 112, 166, 167] or prior exposure of ASM strips ex vivo to cytokines, serum from atopic asthmatics, or immune complexes [113, 168–172]. Studies of ASM cells suggest that the observed ASM hyperreactivity results in part from an increased calcium flux mediated by sensitized Gq- or Gi-coupled receptor transmembrane signaling. Treatment of ASM cells with IL-1β or TNF-α causes a significantly greater increase in phosphoinositide generation and calcium flux elicited by carbachol, bradykinin, or thrombin [173–177]. Mechanistic studies suggest that up-regulated receptor or G protein expression may mediate this enhanced response. IL-1β and TNF-α are both able to increase B2 bradykinin receptor expression in ASM [174, 175]. Treatment of ASM ex vivo with cytokines, rhinovirus, or asthmatic serum [114, 171, 178], in vivo with antigen or IL-1β [112, 179], or ASM cells in culture with TNF-α , has been shown to increase expression of either Gq or specific Gαi isoforms in either lung or ASM. These latter findings are consistent with the observation in ASM cells that calcium mobilization stimulated by NaF (a nonspecific Gα activator) is increased following chronic treatment with TNF-α, and suggest a mechanism by which calcium flux stimulated by numerous GPCRs may be augmented . However, it should be noted that the effects of cytokines on GPCR-mediated PLC activity can be receptor-specific; in the same model that demonstrates TNF-α-mediated augmentation of bradykinin-stimulated phosphoinositide production, the phosphoinositide response to histamine was depressed, presumably via a COX-dependent, PKA-mediated phosphorylation and desensitization of the H1 histamine receptor .
The contribution of desensitized prorelaxant Gs-coupled receptor signaling to airway hyperresponsiveness in asthma is unclear. To date, the β2AR is the only Gs-coupled receptor whose role in asthma has received significant attention, and the preponderance of evidence suggests that β2ARs on ASM are most responsible for the effect of beta-agonists on airway tone . Whether β2AR dysfunction, and specifically β2AR dysfunction in ASM, plays a prominent role in asthma has been a hotly debated topic for over thirty years. Asthma triggers such as viral infections can diminish β2AR function , and numerous animal models of airway inflammation, ex vivo analyses of ASM strips treated with cytokines or asthmatic serum [112, 114], and limited data from ASM tissue from severe asthmatics [184, 185] have all provided evidence that β2AR-mediated relaxant effect and signaling are depressed in asthma. Several possible mechanisms by which the proposed diminished β2AR function and signaling occurs can be proposed. The diminished capacity of beta-agonists to inhibit methacholine-induced contraction of ASM strips ex vivo may reflect an increased capacity of m2 mAChRs to inhibit beta-agonist-stimulated AC activity (note that asthmatic serum and cytokines upregulate Gαi expression). As noted above, several studies also demonstrate that numerous agents (e.g. cytokines, TGF-β, PGE2, whose levels are elevated in the asthmatic airway) induce desensitization of the β2AR in cultured ASM cells, typically by mechanisms suggestive of PKA-mediated β2AR phosphorylation. Moreover, intratracheal installation of IL-1β in rats results in not only a loss of beta-agonist-mediated relaxation of methacholine-induced bronchoconstriction, but an increase in GRK activity, and GRK2 and GRK5 expression in the lung . This is an intriguing finding and suggests that inflammation may modulate homologous GPCR desensitization in the airway. This may preferentially affect β2AR signaling in ASM, in light of findings by McGraw et al. suggesting that low (endogenous) expression levels of GRKs in ASM cells account for relatively robust β2AR signaling in ASM , and that such signaling may be sensitive to changes in GRK  or arrestin  expression.
In contrast to the evidence cited above, numerous studies have noted no appreciable loss of β2AR function in asthmatics based on analyses of lung function, or tissues ex vivo (reviewed in [2, 4, 187]). Moreover, β2AR blockade in normal subjects does not cause bronchoconstriction [188, 189], and the Arg→Gly16 (desensitization-prone) β2AR polymorphism is not over-represented in asthmatics . These findings suggest that asthma is not defined by diminished β2AR responsiveness. However, constitutive β2AR signaling does appear to be important in the asthmatic subject, as administration of β2AR antagonists is not well tolerated in many asthmatic subjects . Predictably, diminished β2AR function could influence disease severity. Results from both clinical trials and epidemiological studies suggest that β2AR SNPs at codon 16 influence β2AR responsiveness to both endogenous and exogenous beta-agonists and thereby influence disease severity and response to therapy [99, 191, 192]. Asthmatics homozygous for Gly16 may have fewer responsive β2ARs as a result of greater down-regulation caused by endogenous catecholamines. Consequently, the effects of endogenous catecholamines and the initial response to exogenous beta-agonist may be diminished in these patients, as suggested by data from Martinez et al., demonstrating a significantly greater bronchodilator response in (beta-agonist naïve) Arg16 homozygotes . Alternatively, continuous use of inhaled beta-agonists results in a progressive drop in morning peak flow only in patients homozygous for the Arg16 SNP , suggesting that the absolute loss of β2AR responsiveness is greater in Arg16 homozygotes because of their greater capacity to down-regulate from the (naïve) untreated state.
Thus the collective evidence suggests that β2AR dysfunction of any nature does not cause asthma, but the active disease state likely promotes a loss of β2AR function that has a small impact on disease severity, at least in some subset of asthmatics. As a corollary, β2AR polymorphisms that diminish β2AR signaling are disease modifiers, but not disease predictors, and influence the response to therapy. In contrast, a more significant role in asthma is suggested for sensitized Gq or Gi-coupled receptor signal transduction that promotes a greater phosphoinositide generation and calcium mobilization in response to a given concentration of agonist.
Altered responsiveness of the contractile machinery to calcium
On a final level we can propose a role for altered responsiveness of ASM contractile machinery to calcium as a mechanism of airway hyperresponsiveness. Although Rho-mediated sensitization to calcium occurs within the context of ASM contraction under normal conditions, there is evidence that calcium sensitization mechanisms may be primed ("augmented sensitization") by inflammation. Chiba et al. noted that acetylcholine-induced isometric tension was greater in bronchial rings from antigen-challenged rats compared to that from control rats, although no significant difference between the two groups in calcium mobilization is observed . Similarly, when calcium concentrations were clamped to 1 μM in permeabilized bronchial rings, tension development was greater in rings from allergen sensitized/challenged rats compared to that from controls . Changes in the expression of numerous proteins may underlie this augmentation of calcium sensitization in ASM. In tracheal and bronchial smooth muscle from ragweed-sensitized dogs, a constitutive increase in phosphorylation of myosin light chain 20 (MLC20) associated with increased content and activity of MLCK [195, 196], and human bronchial rings sensitized with allergen ex vivo exhibit an ~3 fold increase in MLCK expression . RhoA protein levels are increased, and acetylcholine-induced translocation of RhoA to the plasma membrane is significantly higher in bronchial smooth muscle from airway hyperresponsive versus control rats [70, 198]. Finally, Gα12 and Gα13 (upstream regulators of Rho activity) levels in bronchial smooth muscle are also upregulated in hyperresponsive rats . These data suggest that allergen-driven inflammation up-regulates multiple proteins in the pathway promoting Rho-dependent calcium sensitization, and that augmented calcium sensitization may be sufficient to confer airway hyperreactivity in asthma.
Altered GPCR responsiveness with therapy
To further complicate the relationship between GPCR responsiveness and asthma, evidence suggests that both glucocorticoids and beta-agonists, the two most widely used drugs in the treatment of asthma, also regulate GPCR responsiveness, primarily via changes in receptor expression and coupling. Glucocorticoids have been shown to up-regulate β2AR and Gαs expression [89, 91, 199], counteract the β2AR down-regulation induced by beta-agonist , and reverse increases in GRK activity and β2AR desensitization induced in a rat model of airway inflammation . Conversely, glucocorticoids inhibit expression of NK2 receptors in bovine ASM , inhibit m2 mAChR expression in the airway , and inhibit the IL-1β-mediated up-regulation of B2 bradykinin (BK) receptors in the airway . Pretreatment of human ASM cells with glucocorticoids significantly inhibits histamine-stimulated phosphoinositide production . Thus the sum of effects of glucocorticoids on GPCR signal transduction components tends to render ASM less responsive to procontractile stimuli and more responsiveness to beta-agonists.
Beta-agonist therapy, on the other hand, tends to promote the sensitization of procontractile GPCR signaling and desensitization of prorelaxant GPCR signaling, with uncertain clinical relevance. Although conflicting data exist as to whether beta-agonist therapy exacerbates bronchial hyperresponsiveness in asthmatics, Mak and colleagues have recently demonstrated that exposure of ASM ex vivo to beta-agonist up-regulates both NK2  and H1 histamine  receptors, suggesting a mechanism whereby enhanced procontractile GPCR signaling promotes bronchial hyperresponsiveness.
Numerous studies have also demonstrated that repeated use of inhaled beta-agonists results in a loss of the prophylactic bronchoprotection conferred by beta-agonists [203–206]. In many respects this could be considered a normal and predictable response, consistent with a physiologic/teleologic role of β2AR desensitization and the demonstration of homologous desensitization of ASM β2ARs in multiple in vivo, ex vivo, and in vitro models. However, Finney et al. recently observed that lung GRK2 levels were elevated in rats chronically treated with beta-agonists . Thus, in a manner similar to that invoked by IL-1β (see above), chronic beta-agonist therapy may up regulate the GPCR desensitization "machinery" to further limit the effect of therapy and possibly exacerbate disease.
Although the clinical relevance of the observed loss of bronchoprotection has been questioned , the collective evidence suggests that homologous β2AR desensitization does occur as a consequence of beta-agonist therapy. Accordingly, therapies that minimize or counteract β2AR desensitization, such as glucocorticoids and salmeterol, may benefit from this property. Glucocorticoids preserve or enhance β2AR function in the airway through both their anti-inflammatory actions as well as their direct effects on ASM β2AR expression and regulation noted above. These effects may explain in part the positive cooperativity exhibited by combined beta-agonist and glucocorticoids therapy. As a low intrinsic activity beta agonist, salmeterol has limited capacity to promote homologous β2AR desensitization in in vitro models [208, 209]; this property in addition to its lipophilic nature appears largely responsible for its long-lasting effect. Moreover, daily salmeterol treatment has little effect on the rescue or prophylactic ability of albuterol [203, 210].
GPCRs in ASM: What lies ahead
Within the last decade the field of GPCR signaling has experienced an epiphany with the realization that GPCRs do more than subserve restricted functions in fully differentiated cells; they also play important roles in mediating diverse cell functions such as embryogenesis, tissue regeneration, and cell proliferation [211, 212]. Interestingly, this realization coincided with a similarly profound discovery in the field of asthma research – that ASM not only contracts, but also performs numerous "synthetic" functions that modulate both airway structure and airway inflammation. Not surprisingly, ASM GPCRs are important regulators of many ASM synthetic functions.
The newfound respective focuses of GPCR signaling and ASM research suggest an exciting direction for the study of GPCRs in ASM over the next decade. The current challenge (or curse) confronting the student of ASM signal transduction extends beyond defining the myriad intracellular signaling pathways, their regulation, and their degree of "cross-talk" with each other, to understanding how these events occur within an equally complex, dynamic airway environment.
Such an understanding should not only greatly improve our knowledge of asthma pathogenesis, but also redefine asthma therapy. With the possible exception of steroids, asthma drugs have been developed and prescribed to prevent or reverse acute bronchospasm with little consideration of their effects on ASM synthetic functions and the chronic nature of asthma. As the roles of airway remodeling and ASM synthetic functions in asthma pathogenesis become more clearly established, agents that target the activation or signaling of various GPCRs that mediate these phenomena will undoubtedly receive greater consideration as prophylactic and therapeutic asthma drugs.
airway smooth muscle
cysteinyl leukotriene type I receptor
endothelium differentiation gene
epidermal growth factor
Guanine nucleotide exchange factor
G protein-coupled receptor
G protein-coupled receptor kinase
- IP3 :
muscarinic acetylcholine receptor
myosin light chain
myosin light chain kinase
myosin light chain phosphatase
platelet derived growth factor
- PGE2 :
protein kinase A
protein kinase C
regulators of G protein signaling
single nucleotide polymorphism
transforming growth factor beta
tumor necrosis factor alpha
thromboxane A2 / prostaglandin
vasoactive intestinal peptide
The authors wish to thank numerous investigators including Jim Martin and Judith Mak for providing thoughtful discussion, and Stuart Hirst, Dennis McGraw, Andrew Halayko, Steve Liggett, Steve Peters, and Ian Hall for their critical review of the manuscript and contributions leading to its final form. The authors would also like to acknowledge the contributions of Emma Weaver, who was largely responsible for figure generation, and for whom we have reserved a place in our lab as soon as she graduates from high school, college, and medical school. At that time we hope she will be supported by NIH grants HL58506, HL65338, and HL67663. R.B.P. is recipient of an American Lung Association Career Investigator Award.
- Penn RB, Pronin AP, Benovic JL: Regulation of G protein-coupled receptor kinases. Trends Cardiovasc Med 2000, 10:81–89.PubMedView ArticleGoogle Scholar
- Barnes PJ: Pharmacology of airway smooth muscle. Am J Respir Crit Care Med 1998,158(Suppl):S123-S132.PubMedView ArticleGoogle Scholar
- Hall IP: Second messengers, ion channels and pharmacology of airway smooth muscle. Eur Respir J 2000, 15:1120–1127.PubMedView ArticleGoogle Scholar
- Douglas JS: Receptors on target cells. Receptors on airway smooth muscle. Am Rev Respir Dis 1990,141(Suppl):S123-S126.PubMedView ArticleGoogle Scholar
- Tschumperlin DJ, Drazen JM: Mechanical stimuli to airway remodeling. Am J Respir Crit Care Med 2001,164(Suppl):S90-S94.PubMedView ArticleGoogle Scholar
- Bjorck T, Gustafsson LE, Dahlen SE: Isolated bronchi from asthmatics are hyperresponsive to adenosine, which apparently acts indirectly by liberation of leukotrienes and histamine. Am Rev Respir Dis 1992, 145:1087–1091.PubMedView ArticleGoogle Scholar
- Forsythe P, Ennis M: Adenosine, mast cells and asthma. Inflamm Res 1999, 48:301–307.PubMedView ArticleGoogle Scholar
- Salvatore CA, Tilley SL, Latour AM, Fletcher DS, Koller BH, Jacobson MA: Disruption of the A adenosine receptor gene in mice and its effect on stimulated inflammatory cells. J Biol Chem 2000, 275:4429–4434.PubMedView ArticleGoogle Scholar
- Tilley SL, Wagoner VA, Salvatore CA, Jacobson MA, Koller BH: Adenosine and inosine increase cutaneous vasopermeability by activating A receptors on mast cells. J Clin Invest 2000, 105:361–367.PubMedPubMed CentralView ArticleGoogle Scholar
- Feoktistov I, Garland EM, Goldstein AE, Zeng D, Belardinelli L, Wells JN, Biaggioni I: Inhibition of human mast cell activation with the novel selective adenosine A(2B) receptor antagonist 3-isobutyl-8-pyrrolidinoxanthine (IPDX). Biochem Pharmacol 2001, 62:1163–1173.PubMedView ArticleGoogle Scholar
- Zhong H, Chunn JL, Volmer JB, Fozard JR, Blackburn MR: Adenosine-mediated mast cell degranulation in adenosine deaminase-deficient mice. J Pharmacol Exp Ther 2001, 298:433–440.PubMedGoogle Scholar
- Hall IP, Kotlikoff M: Use of cultured airway myocytes for study of airway smooth muscle. Am J Physiol 1995, 268:L1-L11.PubMedGoogle Scholar
- Panettieri RA, Murray RK, DePalo LR, Yadvish PA, Kotlikoff MI: A human smooth muscle cell line that retains physiological responsiveness. Am J Physiol 1989,256(Cell Physiol 25):C329-C335.PubMedGoogle Scholar
- Murray RK, Fleischmann BK, Kotlikoff MI: Receptor-activated Ca2+ influx in human airway smooth muscle: use of Ca2+ imaging and perforated patch-clamp techniques. Am J Physiol 1993,264(Cell Physiol 33):C485-C490.PubMedGoogle Scholar
- McGraw DW, Forbes SL, Kramer LA, Witte DP, Fortner CN, Paul RJ, Liggett SB: Transgenic overexpression of beta-adrenergic receptors in airway smooth muscle alters myocyte function and ablates bronchial hyperreactivity. J Biol Chem 1999, 274:32241–32247.PubMedView ArticleGoogle Scholar
- Neubig RR: Membrane organization in G-protein mechanisms. FASEB J 1994, 8:939–946.PubMedGoogle Scholar
- Ostrom RS, Post SR, Insel PA: Stoichiometry and compartmentation in G protein-coupled receptor signaling: implications for therapeutic interventions involving G(s). J Pharmacol Exp Ther 2000, 294:407–412.PubMedGoogle Scholar
- Ediger TL, Danforth BL, Toews ML: Lysophosphatidic acid upregulates the epidermal growth factor receptor in human airway smooth muscle cells. Am J Physiol Lung Cell Mol Physiol 2002, 282:L91-L98.PubMedGoogle Scholar
- Krymskaya VP, Orsini MJ, Eszterhas A, Benovic JL, Panettieri RA, Penn RB: Potentiation of human airway smooth muscle proliferation by Receptor Tyrosine Kinase and G protein-coupled receptor activation. Am J Respir Cell Mol Biol 2000, 23:546–554.PubMedView ArticleGoogle Scholar
- Penn RB, Pascual RM, Kim Y-M, Mundell SJ, Krymskaya VP, Panettieri RA Jr, Benovic JL: Arrestin specificity for G protein-coupled receptors in human airway smooth muscle. J Biol Chem 2001, 276:32648–32656.PubMedView ArticleGoogle Scholar
- Widdop S, Daykin K, Hall IP: Expression of muscarinic M2 receptors in cultured human airway smooth muscle cells. Am J Respir Cell Mol Biol 1993, 9:541–546.PubMedView ArticleGoogle Scholar
- Halayko AJ, Salari H, Ma X, Stephens NL: Markers of airway smooth muscle cell phenotype. Am J Physiol 1996, 270:L1040-L1051.PubMedGoogle Scholar
- Hubmayr RD, Shore SA, Fredberg JJ, Planus E, Panettieri RA Jr, Moller W, Heyder J, Wang N: Pharmacological activation changes stiffness of cultured human airway smooth muscle cells. Am J Physiol 1996, 271:C1660-C1668.PubMedGoogle Scholar
- Stephens NL, Li W, Wang Y, Ma X: The contractile apparatus of airway smooth muscle. Biophysics and biochemistry. Am J Respir Crit Care Med 1998, 158:S80-S94.PubMedView ArticleGoogle Scholar
- Mitchell RW, Halayko AJ, Kahraman S, Solway J, Wylam ME: Selective restoration of calcium coupling to muscarinic M receptors in contractile cultured airway myocytes. Am J Physiol Lung Cell Mol Physiol 2000, 278:L1091-L1100.PubMedGoogle Scholar
- Camoretti-Mercado B, Liu HW, Halayko AJ, Forsythe SM, Kyle JW, Li B, Fu Y, McConville J, Kogut P, Vieira JE, Patel NM, Hershenson MB, Fuchs E, Sinha S, Miano JM, Parmacek MS, Burkhardt JK, Solway J: Physiological control of smooth muscle-specific gene expression through regulated nuclear translocation of serum response factor. J Biol Chem 2000, 275:30387–30393.PubMedView ArticleGoogle Scholar
- Halayko AJ, Solway J: Molecular mechanisms of phenotypic plasticity in smooth muscle cells. J Appl Physiol 2001, 90:358–368.PubMedGoogle Scholar
- Johnson EN, Druey KM: Heterotrimeric G protein signaling: role in asthma and allergic inflammation. J Allergy Clin Immunol 2002, 109:592–602.PubMedView ArticleGoogle Scholar
- Rhee SG: Regulation of phosphoinositide-specific phospholipase C. Annu Rev Biochem 2001, 70:281–312.PubMedPubMed CentralView ArticleGoogle Scholar
- Pohl J, Winder SJ, Allen BG, Walsh MP, Sellers JR, Gerthoffer WT: Phosphorylation of calponin in airway smooth muscle. Am J Physiol 1997, 272:L115-L123.PubMedGoogle Scholar
- Hakonarson H, Grunstein MM: Regulation of second messengers associated with airway smooth muscle contraction and relaxation. Am J Respir Crit Care Med 1998, 158:S115-S122.PubMedView ArticleGoogle Scholar
- Giembycz MA, Raeburn D: Current concepts on mechanisms of force generation and maintenance in airways smooth muscle. Pulm Pharmacol 1992, 5:279–297.PubMedView ArticleGoogle Scholar
- Somlyo AP, Somlyo AV: Signal transduction and regulation in smooth muscle. Nature 1994, 372:231–236.PubMedView ArticleGoogle Scholar
- Hauck RW, Schulz C, Schomig A, Hoffman RK, Panettieri RA Jr: alpha-Thrombin stimulates contraction of human bronchial rings by activation of protease-activated receptors. Am J Physiol 1999, 277:L22-L29.PubMedGoogle Scholar
- Toews ML, Ediger TL, Romberger DJ, Rennard SI: Lysophosphatidic acid in airway function and disease. Biochim Biophys Acta 2002, 1582:240–250.PubMedView ArticleGoogle Scholar
- Page K, Hershenson MB: Mitogen-activated signaling and cell cycle regulation in airway smooth muscle. Front Biosci 2000, 5:D258-D267.PubMedView ArticleGoogle Scholar
- Krymskaya VP, Penn RB, Orsini MJ, Scott PH, Plevin RJ, Walker TR, Eszterhas AJ, Amrani Y, Chilvers ER, Panettieri RA Jr: Phosphatidylinositol 3-kinase mediates mitogen-induced human airway smooth muscle cell proliferation. Am J Physiol 1999, 277:L65-L78.PubMedGoogle Scholar
- Ammit AJ, Hastie AT, Edsall LC, Hoffman RK, Amrani Y, Krymskaya VP, Kane SA, Peters SP, Penn RB, Spiegel S, Panettieri RA Jr: Sphingosine 1-phosphate modulates human airway smooth muscle cell functions that promote inflammation and airway remodeling in asthma. FASEB J 2001, 15:1212–1214.PubMedGoogle Scholar
- Pang L, Knox AJ: PGE2 release by bradykinin in human airway smooth muscle cells: involvement of cyclooxygenase-2 induction. Am J Physiol 1997, 273:L1132-L1140.PubMedGoogle Scholar
- Hirshman CA, Emala CW: Actin reorganization in airway smooth muscle cells involves Gq and Gi-2 activation of Rho. Am J Physiol 1999, 277:L653-L661.PubMedGoogle Scholar
- Belvisi MG, Saunders M, Yacoub M, Mitchell JA: Expression of cyclo-oxygenase-2 in human airway smooth muscle is associated with profound reductions in cell growth. Br J Pharmacol 1998, 125:1102–1108.PubMedPubMed CentralView ArticleGoogle Scholar
- Mundell SJ, Olah ME, Panettieri RA, Benovic JL, Penn RB: Regulation of G protein-coupled receptor-adenylyl cyclase responsiveness in human airway smooth muscle by exogenous and endogenous adenosine. Am J Respir Cell Mol Biol 2000, 24:155–163.View ArticleGoogle Scholar
- Maruno K, Absood A, Said SI: VIP inhibits basal and histamine-stimulated proliferation of human smooth muscle cells. American Journal of Physiology 1995, 268:L1047-L1051.PubMedGoogle Scholar
- Penn RB, Benovic JL: Regulation of G protein-coupled receptors. In Handbook of Physiology (Edited by: Conn PM). New York: Oxford University Press 1998, 125–164.Google Scholar
- Premont RT: Identification of adenylyl cyclases by amplification using degenerate primers. Methods Enzymol 1994, 238:116–127.PubMedView ArticleGoogle Scholar
- Billington CK, Hall IP, Mundell SM, Parent J-L, Panettieri RA, Benovic JL, Penn RB: Inflammatory and contractile agents sensitize specific adenylyl cyclase isoforms in human airway smooth muscle. Am J Resp Cell Mol Biol 1999, 21:597–606.View ArticleGoogle Scholar
- Xu D, Isaacs C, Hall IP, Emala CW: Human airway smooth muscle expresses 7 isoforms of adenylyl cyclase: a dominant role for isoform V. Am J Physiol Lung Cell Mol Physiol 2001, 281:L832-L843.PubMedGoogle Scholar
- Stevens PA, Pyne S, Grady M, Pyne NJ: Bradykinin-dependent activation of adenylate cyclase activity and cyclic AMP accumulation in tracheal smooth muscle occurs via protein kinase C-dependent and -independent pathways. Biochem J 1994, 297:233–239.PubMedPubMed CentralView ArticleGoogle Scholar
- Pyne NJ, Moughal N, Stevens PA, Tolan D, Pyne S: Protein kinase C-dependent cyclic AMP formation in airway smooth muscle: the role of type II adenylate cyclase and the blockade of extracellular-signal-regulated kinase-2 (ERK-2) activation. Biochemical J 1994, 304:611–616.View ArticleGoogle Scholar
- Emala CW, Clancy-Keen J, Hirshman CA: Decreased adenylyl cyclase protein and function in airway smooth muscle by chronic carbachol pretreatment. Am J Physiol Cell Physiol 2000, 279:C1008-C1015.PubMedGoogle Scholar
- Schears G, Clancy J, Hirshman CA, Emala CW: Chronic carbachol pretreatment decreases adenylyl cyclase activity in airway smooth muscle. Am J Physiol 1997, 273:L640–7.PubMedGoogle Scholar
- Taussig R, Zimmermann G: Type-specific regulation of mammalian adenylyl cyclases by G protein pathways. Adv Second Messenger Phosphoprotein Res 1998, 32:81–98.PubMedView ArticleGoogle Scholar
- Hallsworth MP, Twort CH, Lee TH, Hirst SJ: beta-adrenoceptor agonists inhibit release of eosinophil-activating cytokines from human airway smooth muscle cells. Br J Pharmacol 2001, 132:729–741.PubMedPubMed CentralView ArticleGoogle Scholar
- Ammit AJ, Hoffman RK, Amrani Y, Lazaar AL, Hay DWP, Torphy TJ, Penn RB, Panettieri RA: TNFa-induced secretion of RANTES and IL-6 from human airway smooth muscle cells: Modulation by cAMP. Am J Respir Cell Mol Biol 2000, 23:794–802.PubMedView ArticleGoogle Scholar
- Hirshman CA, Zhu D, Panettieri RA, Emala CW: Actin depolymerization via the beta-adrenoceptor in airway smooth muscle cells: a novel PKA-independent pathway. Am J Physiol Cell Physiol 2001, 281:C1468-C1476.PubMedGoogle Scholar
- Kume H, Hall IP, Washabau RJ, Tagaki K, Kotlikoff MI: b-adrenergic agonists regulate KCa channels in airway smooth muscle by cAMP-dependent and -independent mechanisms. J Clin Invest 1994, 93:371–379.PubMedPubMed CentralView ArticleGoogle Scholar
- Spicuzza L, Belvisi MG, Birrell MA, Barnes PJ, Hele DJ, Giembycz MA: Evidence that the anti-spasmogenic effect of the beta-adrenoceptor agonist, isoprenaline, on guinea-pig trachealis is not mediated by cyclic AMP-dependent protein kinase. Br J Pharmacol 2001, 133:1201–1212.PubMedPubMed CentralView ArticleGoogle Scholar
- Mak JCW, HIsada T, Salmon PJ, Barnes PJ, Chung KF: Reversal of IL-1beta-induced up-regulation of G-protein-coupled receptor kinase activity by dexamethasone. Am J Respir Care Crit Med 2001, 163:A228.Google Scholar
- Joshi S, Abebe W, Agrawal DK: Identification of guanine nucleotide binding regulatory proteins in bovine tracheal smooth muscle. Mol Cell Biochem 1996, 154:179–184.PubMedView ArticleGoogle Scholar
- Zaagsma J, Roffel AF, Meurs H: Muscarinic control of airway function. Life Sci 1997, 60:1061–1068.PubMedView ArticleGoogle Scholar
- Chiba Y, Sakai H, Misawa M: Possible involvement of G(i3) protein in augmented contraction of bronchial smooth muscle from antigen-induced airway hyperresponsive rats. Biochem Pharmacol 2001, 61:921–924.PubMedView ArticleGoogle Scholar
- Thomas JM, Hoffman BB: Isoform-specific sensitization of adenylyl cyclase activity by prior activation of inhibitory receptors: role of beta gamma subunits in transducing enhanced activity of the type VI isoform. Mol Pharmacol 1996, 49:907–914.PubMedGoogle Scholar
- Prather PL, Tsai AW, Law PY: Mu and delta opioid receptor desensitization in undifferentiated human neuroblastoma SHSY5Y cells. Mol Pharmacol 1994, 270:177–184.Google Scholar
- Nestler EJ, Hope BT, Widnell KL: Drug addiction: a model for the molecular basis of neural plasticity. Neuron 1993, 11:995–1006.PubMedView ArticleGoogle Scholar
- Zadina JE, Harrison LM, Ge LJ, Kastin AJ, Chang SL: Differential regulation of mu and delta opiate receptors by morphine, selective agonists and antagonists and differentiating agents in SH-SY5Y human neuroblastoma cells. J Pharmacol Exp Ther 1994, 270:1086–1096.PubMedGoogle Scholar
- Luttrell LM, Della Rocca GJ, van Biesen T, Luttrell DK, Lefkowitz RJ: Gbetagamma subunits mediate Src-dependent phosphorylation of the epidermal growth factor receptor. A scaffold for G protein-coupled receptor-mediated Ras activation. J Biol Chem 1997, 272:4637–4644.PubMedView ArticleGoogle Scholar
- Sah VP, Seasholtz TM, Sagi SA, Brown JH: The role of Rho in G protein-coupled receptor signal transduction. Annu Rev Pharmacol Toxicol 2000, 40:459–489.PubMedView ArticleGoogle Scholar
- Chiba Y, Misawa M: Increased expression of G12 and G13 proteins in bronchial smooth muscle of airway hyperresponsive rats. Inflamm Res 2001, 50:333–336.PubMedView ArticleGoogle Scholar
- Iizuka K, Yoshii A, Samizo K, Tsukagoshi H, Ishizuka T, Dobashi K, Nakazawa T, Mori M: A major role for the rho-associated coiled coil forming protein kinase in G-protein-mediated Ca2+ sensitization through inhibition of myosin phosphatase in rabbit trachea. Br J Pharmacol 1999, 128:925–933.PubMedPubMed CentralView ArticleGoogle Scholar
- Chiba Y, Takada Y, Miyamoto S, MitsuiSaito M, Karaki H, Misawa M: Augmented acetylcholine-induced, Rho-mediated Ca2+ sensitization of bronchial smooth muscle contraction in antigen-induced airway hyperresponsive rats. Br J Pharmacol 1999, 127:597–600.PubMedPubMed CentralView ArticleGoogle Scholar
- Hall IP, Daykin K, Widdop S: Beta 2-adrenoceptor desensitization in cultured human airway smooth muscle. Clin Sci (Colch) 1993, 84:151–157.View ArticleGoogle Scholar
- Penn RB, Panettieri RA Jr, Benovic JL: Mechanisms of acute desensitization of the b2AR-adenylyl cyclase pathway in human airway smooth muscle. Am J Resp Cell Mol Biol 1998, 19:338–348.View ArticleGoogle Scholar
- Lohse MJ, Benovic JL, Codina J, Caron MG, Lefkowitz RJ: Beta-arrestin: a protein that regulates beta-adrenergic receptor function. Science 1990, 248:1547–1550.PubMedView ArticleGoogle Scholar
- Ferguson SS, Downey WE 3rd, Colapietro AM, Barak LS, Menard L, Caron MG: Role of beta-arrestin in mediating agonist-promoted G protein-coupled receptor internalization. Science 1996, 271:363–366.PubMedView ArticleGoogle Scholar
- Goodman OB Jr, Krupnick JG, Santini F, Gurevich VV, Penn RB, Gagnon AW, Keen JH, Benovic JL: Beta-arrestin acts as a clathrin adaptor in endocytosis of the beta2-adrenergic receptor. Nature 1996, 383:447–450.PubMedView ArticleGoogle Scholar
- Huang C, Hepler JR, Chen LT, Gilman AG, Anderson RG, Mumby SM: Organization of G proteins and adenylyl cyclase at the plasma membrane. Mol Biol Cell 1997, 8:2365–2378.PubMedPubMed CentralView ArticleGoogle Scholar
- Laporte JD, Moore PE, Panettieri RA, Moeller W, Heyder J, Shore SA: Prostanoids mediate IL-1beta-induced beta-adrenergic hyporesponsiveness in human airway smooth muscle cells. Am J Physiol 1998, 275:L491-L501.PubMedGoogle Scholar
- Emala CW, Kuhl J, Hungerford CL, Hirshman CA: TNF-alpha inhibits isoproterenol-stimulated adenylyl cyclase activity in cultured airway smooth muscle cells. Am J Physiol 1997, 272:L644-L650.PubMedGoogle Scholar
- Fong CY, Pang L, Holland E, Knox AJ: TGF-beta1 stimulates IL-8 release, COX-2 expression, and PGE release in human airway smooth muscle cells. Am J Physiol Lung Cell Mol Physiol 2000, 279:L201-L207.PubMedGoogle Scholar
- Pang L, Holland E, Knox AJ: Role of cyclo-oxygenase-2 induction in interleukin-1beta induced attenuation of cultured human airway smooth muscle cell cyclic AMP generation in response to isoprenaline. Br J Pharmacol 1998, 125:1320–1328.PubMedPubMed CentralView ArticleGoogle Scholar
- Pype JL, Mak JC, Dupont LJ, Verleden GM, Barnes PJ: Desensitization of the histamine H1-receptor and transcriptional down-regulation of histamine H1-receptor gene expression in bovine tracheal smooth muscle. Br J Pharmacol 1998, 125:1477–1484.PubMedPubMed CentralView ArticleGoogle Scholar
- Gagnon AW, Kallal L, Benovic JL: Role of clathrin-mediated endocytosis in agonist-induced down-regulation of the beta2-adrenergic receptor. J Biol Chem 1998, 273:6976–6981.PubMedView ArticleGoogle Scholar
- Shenoy SK, McDonald PH, Kohout TA, Lefkowitz RJ: Regulation of receptor fate by ubiquitination of activated beta 2-adrenergic receptor and beta-arrestin. Science 2001, 294:1307–1313.PubMedView ArticleGoogle Scholar
- Marchese A, Benovic JL: Agonist-promoted ubiquitination of the G protein-coupled receptor CXCR4 mediates lysosomal sorting. J Biol Chem 2001, 276:45509–45512.PubMedView ArticleGoogle Scholar
- Chaturvedi K, Bandari P, Chinen N, Howells RD: Proteasome involvement in agonist-induced down-regulation of mu and delta opioid receptors. J Biol Chem 2001, 276:12345–12355.PubMedView ArticleGoogle Scholar
- Green SA, Turki J, Bejarano P, Hall IP, Liggett : Influence of b2-adrenergic receptor genotypes on signal transduction in human airway smooth muscle cells. Am J Respir Cell Mol Biol 1995, 13:25–33.PubMedView ArticleGoogle Scholar
- Pype JL, Dupont LJ, Mak JC, Barnes PJ, Verleden GM: Regulation of H1-receptor coupling and H1-receptor mRNA by histamine in bovine tracheal smooth muscle. Br J Pharmacol 1998, 123:984–990.PubMedPubMed CentralView ArticleGoogle Scholar
- Mak JC, Rousell J, Haddad EB, Barnes PJ: Transforming growth factor-beta1 inhibits beta2-adrenoceptor gene transcription. Naunyn Schmiedebergs Arch Pharmacol 2000, 362:520–525.PubMedView ArticleGoogle Scholar
- Kalavantavanich K, Schramm CM: Dexamethasone potentiates high-affinity beta-agonist binding and g(s)alpha protein expression in airway smooth muscle. Am J Physiol Lung Cell Mol Physiol 2000, 278:L1101-L1106.PubMedGoogle Scholar
- Mak JC, Roffel AF, Katsunuma T, Elzinga CR, Zaagsma J, Barnes PJ: Up-regulation of airway smooth muscle histamine H receptor mRNA, protein, and function by beta-adrenoceptor activation. Mol Pharmacol 2000, 57:857–864.PubMedGoogle Scholar
- Mak JC, Nishikawa M, Barnes PJ: Glucocorticosteroids increase beta 2-adrenergic receptor transcription in human lung. Am J Physiol 1995, 268:L41-L46.PubMedGoogle Scholar
- Mak JC, Nishikawa M, Shirasaki H, Miyayasu K, Barnes PJ: Protective effects of a glucocorticoid on downregulation of pulmonary beta 2-adrenergic receptors in vivo. J Clin Invest 1995, 96:99–106.PubMedPubMed CentralView ArticleGoogle Scholar
- Forsythe SM, Kogut PC, McConville JF, Fu Y, McCauley JA, Halayko AJ, Liu HW, Kao A, Fernandes DJ, Bellam S, Fuchs E, Sinha S, Bell GI, Camoretti-Mercado B, Solway J: Structure and transcription of the human m3 muscarinic receptor gene. Am J Respir Cell Mol Biol 2002, 26:298–305.PubMedView ArticleGoogle Scholar
- Katsunuma T, Mak JC, Barnes PJ: Glucocorticoids reduce tachykinin NK2 receptor expression in bovine tracheal smooth muscle. Eur J Pharmacol 1998, 344:99–106.PubMedView ArticleGoogle Scholar
- Katsunuma T, Roffel AF, Elzinga CR, Zaagsma J, Barnes PJ, Mak JC: beta-adrenoceptor agonist-induced upregulation of tachykinin NK receptor expression and function in airway smooth muscle. Am J Respir Cell Mol Biol 1999, 21:409–417.PubMedView ArticleGoogle Scholar
- Koto H, Mak JC, Haddad EB, Xu WB, Salmon M, Barnes PJ, Chung KF: Mechanisms of impaired beta-adrenoceptor-induced airway relaxation by interleukin-1beta in vivo in the rat. J Clin Invest 1996, 98:1780–1787.PubMedPubMed CentralView ArticleGoogle Scholar
- Rousell J, Haddad EB, Mak JC, Webb BL, Giembycz MA, Barnes PJ: Beta-Adrenoceptor-medicated down-regulation of M2 muscarinic receptors: role of cyclic adenosine 5'-monophosphate-dependent protein kinase and protein kinase C. Mol Pharmacol 1996, 49:629–635.PubMedGoogle Scholar
- Witt-Enderby PA, Yamamura HI, Halonen M, Lai J, Palmer JD, Bloom J: Regulation of airway muscarinic cholinergic receptor subtypes by chronic anticholinergic treatment. Mol Pharmacol 1995, 47:485–490.PubMedGoogle Scholar
- Liggett SB: Pharmacogenetics of beta-1- and beta-2-adrenergic receptors. Pharmacology 2000, 61:167–173.PubMedView ArticleGoogle Scholar
- Hall IP: Pharmacogenetics, pharmacogenomics and airway disease. Respir Res 2002, 3:10.PubMedView ArticleGoogle Scholar
- Scott MG, Swan C, Wheatley AP, Hall IP: Identification of novel polymorphisms within the promoter region of the human beta2 adrenergic receptor gene. Br J Pharmacol 1999, 126:841–844.PubMedPubMed CentralView ArticleGoogle Scholar
- McGraw DW, Forbes SL, Kramer LA, Liggett SB: Polymorphisms of the 5' leader cistron of the human beta2-adrenergic receptor regulate receptor expression. J Clin Invest 1998, 102:1927–1932.PubMedPubMed CentralView ArticleGoogle Scholar
- Small KM, Forbes SL, Brown KM, Liggett SB: An asn to lys polymorphism in the third intracellular loop of the human alpha 2A-adrenergic receptor imparts enhanced agonist-promoted Gi coupling. J Biol Chem 2000, 275:38518–38523.PubMedView ArticleGoogle Scholar
- Small KM, Brown KM, Forbes SL, Liggett SB: Polymorphic deletion of three intracellular acidic residues of the alpha 2B-adrenergic receptor decreases G protein-coupled receptor kinase-mediated phosphorylation and desensitization. J Biol Chem 2001, 276:4917–4922.PubMedView ArticleGoogle Scholar
- Mason DA, Moore JD, Green SA, Liggett SB: A gain-of-function polymorphism in a G-protein coupling domain of the human beta1-adrenergic receptor. J Biol Chem 1999, 274:12670–12674.PubMedView ArticleGoogle Scholar
- Rathz DA, Brown KM, Kramer LA, Liggett SB: Amino acid 49 polymorphisms of the human beta1-adrenergic receptor affect agonist-promoted trafficking. J Cardiovasc Pharmacol 2002, 39:155–160.PubMedView ArticleGoogle Scholar
- Ross EM, Wilkie TM: GTPase-activating proteins for heterotrimeric G proteins: regulators of G protein signaling (RGS) and RGS-like proteins. Annu Rev Biochem 2000, 69:795–827.PubMedView ArticleGoogle Scholar
- Carman CV, Parent JL, Day PW, Pronin AN, Sternweis PM, Wedegaertner PB, Gilman AG, Benovic JL, Kozasa T: Selective regulation of Galpha(q/11) by an RGS domain in the G protein-coupled receptor kinase GRK2. J Biol Chem 1999, 274:34483–34492.PubMedView ArticleGoogle Scholar
- Milligan G, Mullaney I, Kim GD, MacEwan D: Regulation of the stoichiometry of protein components of the stimulatory adenylyl cyclase cascade. Adv Pharmacol 1998, 42:462–465.PubMedView ArticleGoogle Scholar
- Finney PA, Belvisi MG, Donnelly LE, Chuang TT, Mak JC, Scorer C, Barnes PJ, Adcock IM, Giembycz MA: Albuterol-induced downregulation of Gsalpha accounts for pulmonary beta-adrenoceptor desensitization in vivo. J Clin Invest 2000, 106:125–135.PubMedPubMed CentralView ArticleGoogle Scholar
- Finney PA, Donnelly LE, Belvisi MG, Chuang TT, Birrell M, Harris A, Mak JC, Scorer C, Barnes PJ, Adcock IM, Giembycz MA: Chronic systemic administration of salmeterol to rats promotes pulmonary beta-adrenoceptor desensitization and down-regulation of G(s alpha). Br J Pharmacol 2001, 132:1261–1270.PubMedPubMed CentralView ArticleGoogle Scholar
- Mak JC, Hisada T, Salmon M, Barnes PJ, Chung KF: Glucocorticoids reverse IL-1beta-induced impairment of beta-adrenoceptor-mediated relaxation and up-regulation of G-protein-coupled receptor kinases. Br J Pharmacol 2002, 135:987–996.PubMedPubMed CentralView ArticleGoogle Scholar
- Hakonarson H, Herrick DJ, Gonzalez Serrano P, Grunstein MM: Mechanism of cytokine-induced modulation of b-adrenoceptor responsiveness in airway smooth muscle. J Clin Invest 1996, 97:2593–2600.PubMedPubMed CentralView ArticleGoogle Scholar
- Hakonarson H, Herrick DJ, Grunstein MM: Mechanism of impaired b-adrenoceptor responsiveness in atopic sensitized airway smooth muscle. Am J Physiol 1995,269(Lung Cell Mol Physiol 13):L645-L652.PubMedGoogle Scholar
- Rebecchi MJ, Pentyala SN: Structure, function, and control of phosphoinositide-specific phospholipase C. Physiol Rev 2000, 80:1291–1335.PubMedGoogle Scholar
- Willars GB, Nahorski SR, Challiss RA: Differential regulation of muscarinic acetylcholine receptor-sensitive polyphosphoinositide pools and consequences for signaling in human neuroblastoma cells. J Biol Chem 1998, 273:5037–5046.PubMedView ArticleGoogle Scholar
- Wang T, Dowal L, El-Maghrabi MR, Rebecchi M, Scarlata S: The pleckstrin homology domain of phospholipase C-beta links the binding of gbetagamma to activation of the catalytic core. J Biol Chem 2000, 275:7466–7469.PubMedView ArticleGoogle Scholar
- Wang T, Pentyala S, Rebecchi MJ, Scarlata S: Differential association of the pleckstrin homology domains of phospholipases C-beta 1, C-beta 2, and C-delta 1 with lipid bilayers and the beta gamma subunits of heterotrimeric G proteins. Biochemistry 1999, 38:1517–1524.PubMedView ArticleGoogle Scholar
- Yue C, Ku CY, Liu M, Simon MI, Sanborn BM: Molecular mechanism of the inhibition of phospholipase C beta 3 by protein kinase C. J Biol Chem 2000, 275:30220–30225.PubMedView ArticleGoogle Scholar
- Liu M, Simon MI: Regulation by cAMP-dependent protein kinase of a G-protein-mediated phospholipase C. Nature 1996, 382:83–87.PubMedView ArticleGoogle Scholar
- Yue C, Dodge KL, Weber G, Sanborn BM: Phosphorylation of serine 1105 by protein kinase A inhibits phospholipase Cbeta3 stimulation by Galphaq. J Biol Chem 1998, 273:18023–18027.PubMedView ArticleGoogle Scholar
- Ryu SH, Kim UH, Wahl MI, Brown AB, Carpenter G, Huang KP, Rhee SG: Feedback regulation of phospholipase C-beta by protein kinase C. J Biol Chem 1990, 265:17941–17945.PubMedGoogle Scholar
- Berstein G, Blank JL, Jhon DY, Exton JH, Rhee SG, Ross EM: Phospholipase C-beta 1 is a GTPase-activating protein for Gq/11, its physiologic regulator. Cell 1992, 70:411–418.PubMedView ArticleGoogle Scholar
- Tolloczko B, Tao FC, Zacour ME, Martin JG: Tyrosine kinase-dependent calcium signaling in airway smooth muscle cells. Am J Physiol Lung Cell Mol Physiol 2000, 278:L1138-L1145.PubMedGoogle Scholar
- Tao FC, Tolloczko B, Mitchell CA, Powell WS, Martin JG: Inositol (1,4,5)trisphosphate metabolism and enhanced calcium mobilization in airway smooth muscle of hyperresponsive rats. Am J Respir Cell Mol Biol 2000, 23:514–520.PubMedView ArticleGoogle Scholar
- Tolloczko B, Turkewitsch P, Choudry S, Bisotto S, Fixman ED, Martin JG: Src modulates serotonin-induced calcium signaling by regulating phosphatidylinositol 4,5-bisphosphate. Am J Physiol Lung Cell Mol Physiol 2002, 282:L1305-L1313.PubMedView ArticleGoogle Scholar
- Pyne S, Pyne NJ: Bradykinin-stimulated phosphatidylcholine hydrolysis in airway smooth muscle: the role of Ca2+ and protein kinase C. Biochem J 1995, 311:637–642.PubMedPubMed CentralView ArticleGoogle Scholar
- Taussig R, Gilman AG: Mammalian membrane-bound adenylyl cyclases. J Biol Chem 1995, 270:1–4.PubMedView ArticleGoogle Scholar
- Smit MJ, Iyengar R: Mammalian adenylyl cyclases. Adv Second Messenger Phosphoprotein Res 1998, 32:1–21.PubMedView ArticleGoogle Scholar
- Choi EJ, Wong ST, Dittman AH, Storm DR: Phorbol ester stimulation of the type I and type III adenylyl cyclases in whole cells. Biochemistry 1993, 32:1891–1894.PubMedView ArticleGoogle Scholar
- Kawabe J, Ebina T, Toya Y, Oka N, Schwencke C, Duzic E, Ishikawa Y: Regulation of type V adenylyl cyclase by PMA-sensitive and -insensitive protein kinase C isoenzymes in intact cells. FEBS Lett 1996, 384:273–276.PubMedView ArticleGoogle Scholar
- Kawabe J, Iwami G, Ebina T, Ohno S, Katada T, Ueda Y, Homcy CJ, Ishikawa Y: Differential activation of adenylyl cyclase by protein kinase C isoenzymes. J Biol Chem 1994, 269:16554–16558.PubMedGoogle Scholar
- Jacobowitz O, Iyengar R: Phorbol ester-induced stimulation and phosphorylation of adenylyl cyclase 2. Proc Natl Acad Sci U S A 1994, 91:10630–10634.PubMedPubMed CentralView ArticleGoogle Scholar
- Yoshimura M, Cooper DM: Type-specific stimulation of adenylyl cyclase by protein kinase C. J Biol Chem 1993, 268:4604–4607.PubMedGoogle Scholar
- Premont RT, Jacobowitz O, Iyengar R: Lowered responsiveness of the catalyst of adenylyl cyclase to stimulation by GS in heterologous desensitization: a role for adenosine 3',5'-monophosphate-dependent phosphorylation. Endocrinology 1992, 131:2774–2784.PubMedGoogle Scholar
- Murthy KS, Zhou H, Makhlouf GM: PKA-dependent activation of PDE3A and PDE4 and inhibition of adenylyl cyclase V/VI in smooth muscle. Am J Physiol Cell Physiol 2002, 282:C508-C517.PubMedView ArticleGoogle Scholar
- Iwami G, Kawabe J, Ebina T, Cannon PJ, Homcy CJ, Ishikawa Y: Regulation of adenylyl cyclase by protein kinase A. J Biol Chem 1995, 270:12481–12484.PubMedView ArticleGoogle Scholar
- Federman AD, Conklin BR, Schrader KA, Reed RR, Bourne HR: Hormonal stimulation of adenylyl cyclase through Gi-protein beta gamma subunits. Nature 1992, 356:159–161.PubMedView ArticleGoogle Scholar
- Tang W-J, Gilman AG: Type-specific regulation of adenylyl cyclase by G protein bg subunits. Science 1991, 254:1500–1503.PubMedView ArticleGoogle Scholar
- Gao B, Gilman AG: Cloning and expression of a widely distributed (type IV) adenylyl cyclase. Proc Natl Acad Sci USA 1991, 89:10178–10182.View ArticleGoogle Scholar
- Ostrom RS: New determinants of receptor-effector coupling: trafficking and compartmentation in membrane microdomains. Mol Pharmacol 2002, 61:473–476.PubMedView ArticleGoogle Scholar
- Ostrom RS, Gregorian C, Drenan RM, Xiang Y, Regan JW, Insel PA: Receptor number and caveolar co-localization determine receptor coupling efficiency to adenylyl cyclase. J Biol Chem 2001, 276:42063–42069.PubMedView ArticleGoogle Scholar
- Hope HR, Pike LJ: Phosphoinositides and phosphoinositide-utilizing enzymes in detergent-insoluble lipid domains. Mol Biol Cell 1996, 7:843–851.PubMedPubMed CentralView ArticleGoogle Scholar
- Pyne NJ, Pyne S: PDGF-stimulated cyclic AMP formation in airway smooth muscle: assessment of the roles of MAP kinase, cytosolic phospholipase A2, and arachidonate metabolites. Cell Signal 1998, 10:363–369.PubMedView ArticleGoogle Scholar
- Lampert A, Nirenberg M, Klee WA: Tolerance and dependence evoked by an endogenous opioid peptide. Proc Natl Acad Sci USA 1976, 73:3165–3167.PubMedPubMed CentralView ArticleGoogle Scholar
- Zadina JE, Chang SL, Ge LJ, Kastin AJ: Mu opiate receptor down-regulation by morphine and up-regulation by naxolone in SH-SY5Y human neuroblastoma cells. J Pharmacol Exp Ther 1993, 265:254–262.PubMedGoogle Scholar
- Nevo I, Avidor-Reiss T, Levy R, Bayewitch M, Heldman E, Vogel Z: Regulation of adenylyl cyclase isozymes on acute and chronic activation of inhibitory receptors. Mol Pharmacol 1998, 54:419–426.PubMedGoogle Scholar
- Lemanske RF Jr, Busse WW: Asthma. JAMA 1997, 278:1855–1873.PubMedView ArticleGoogle Scholar
- Chiappara G, Gagliardo R, Siena A, Bonsignore MR, Bousquet J, Bonsignore G, Vignola AM: Airway remodelling in the pathogenesis of asthma. Curr Opin Allergy Clin Immunol 2001, 1:85–93.PubMedView ArticleGoogle Scholar
- Fahy JV, Corry DB, Boushey HA: Airway inflammation and remodeling in asthma. Curr Opin Pulm Med 2000, 6:15–20.PubMedView ArticleGoogle Scholar
- Hirst SJ, Walker TR, Chilvers ER: Phenotypic diversity and molecular mechanisms of airway smooth muscle proliferation in asthma. Eur Respir J 2000, 16:159–177.PubMedView ArticleGoogle Scholar
- Jeffery PK: Morphology of the airway wall in asthma and in chronic obstructive pulmonary disease. Am Rev Respir Dis 1991, 143:1152–1158.PubMedView ArticleGoogle Scholar
- Stewart AG: Airway wall remodelling and hyperresponsiveness: modelling remodelling in vitro and in vivo. Pulm Pharmacol Ther 2001, 14:255–265.PubMedView ArticleGoogle Scholar
- Martin JG, Duguet A, Eidelman DH: The contribution of airway smooth muscle to airway narrowing and airway hyperresponsiveness in disease. Eur Respir J 2000, 16:349–354.PubMedView ArticleGoogle Scholar
- Sofia M, Mormile M, Faraone S, Alifano M, Zofra S, Romano L, Carratu L: Increased endothelin-like immunoreactive material on bronchoalveolar lavage fluid from patients with bronchial asthma and patients with interstitial lung disease. Respiration 1993, 60:89–95.PubMedView ArticleGoogle Scholar
- Panettieri RA: Airway smooth muscle cell growth and proliferation. In Airway Smooth Muscle: Development, Regulation, and Contractility (Edited by: Raeburn D, Giembycz MA). Basel: Birkhauser Verlag 1994, 41–68.View ArticleGoogle Scholar
- Zehr BB, Casale TB, Wood D, Floerchinger C, Richerson HB, Hunninghake GW: Use of segmental airway lavage to obtain relevant mediators from the lungs of asthmatic and control subjects. Chest 1989, 95:1059–1063.PubMedView ArticleGoogle Scholar
- Casale TB, Wood D, Richerson HB, Trapp S, Metzger WJ, Zavala D, Hunninghake GW: Elevated bronchoalveolar lavage fluid histamine levels in allergic asthmatics are associated with methacholine bronchial hyperresponsiveness. J Clin Invest 1987, 79:1197–1203.PubMedPubMed CentralView ArticleGoogle Scholar
- Ackerman V, Carpi S, Bellini A, Vassalli G, Marini M, Mattoli S: Constitutive expression of endothelin in bronchial epithelial cells of patients with symptomatic and asymptomatic asthma and modulation by histamine and interleukin-1. J Allergy Clin Immunol 1995, 96:618–627.PubMedView ArticleGoogle Scholar
- Hamilton LM, Davies DE, Wilson SJ, Kimber I, Dearman RJ, Holgate ST: The bronchial epithelium in asthma – much more than a passive barrier. Monaldi Arch Chest Dis 2001, 56:48–54.PubMedGoogle Scholar
- Holgate ST: Epithelial damage and response. Clin Exp Allergy 2000,30(Suppl 1):37–41.PubMedView ArticleGoogle Scholar
- Frossard N, Stretton CD, Barnes PJ: Modulation of bradykinin responses in airway smooth muscle by epithelial enzymes. Agents Actions 1990, 31:204–209.PubMedView ArticleGoogle Scholar
- Knight DA, Adcock JA, Phillips MJ, Thompson PJ: The effect of epithelium removal on human bronchial smooth muscle responsiveness to acetylcholine and histamine. Pulm Pharmacol 1990, 3:198–202.PubMedView ArticleGoogle Scholar
- Raeburn D: Putative role of epithelial derived factors in airway smooth muscle reactivity. Agents Actions Suppl 1990, 31:259–274.PubMedGoogle Scholar
- Amrani Y, Panettieri RA Jr: Modulation of calcium homeostasis as a mechanism for altering smooth muscle responsiveness in asthma. Curr Opin Allergy Clin Immunol 2002, 2:39–45.PubMedView ArticleGoogle Scholar
- Cui ZH, Skoogh BE, Pullerits T, Lotvall J: Bronchial hyperresponsiveness and airway wall remodelling induced by exposure to allergen for 9 weeks. Allergy 1999, 54:1074–1082.PubMedView ArticleGoogle Scholar
- Patel HJ, Douglas GJ, Herd CM, Spina D, Giembycz MA, Barnes PJ, Belvisi MG, Page CP: Antigen-induced bronchial hyperresponsiveness in the rabbit is not dependent on M-receptor dysfunction. Pulm Pharmacol Ther 1999, 12:245–255.PubMedView ArticleGoogle Scholar
- Schmidt D, Ruehlmann E, Branscheid D, Magnussen H, Rabe KF: Passive sensitization of human airways increases responsiveness to leukotriene C4. Eur Respir J 1999, 14:315–319.PubMedView ArticleGoogle Scholar
- Grunstein MM, Hakonarson H, Leiter J, Chen M, Whelan R, Grunstein JS, Chuang S: IL-13-dependent autocrine signaling mediates altered responsiveness of IgE-sensitized airway smooth muscle. Am J Physiol Lung Cell Mol Physiol 2002, 282:L520-L528.PubMedView ArticleGoogle Scholar
- Hakonarson H, Herrick DJ, Serrano PG, Grunstein MM: Autocrine role of interleukin 1beta in altered responsiveness of atopic asthmatic sensitized airway smooth muscle. J Clin Invest 1997, 99:117–124.PubMedPubMed CentralView ArticleGoogle Scholar
- Hakonarson H, Maskeri N, Carter C, Hodinka RL, Campbell D, Grunstein MM: Mechanism of rhinovirus-induced changes in airway smooth muscle responsiveness. J Clin Invest 1998, 102:1732–1741.PubMedPubMed CentralView ArticleGoogle Scholar
- Hakonarson H, Carter C, Kim C, Grunstein MM: Altered expression and action of the low-affinity IgE receptor FcepsilonRII (CD23) in asthmatic airway smooth muscle. J Allergy Clin Immunol 1999, 104:575–584.PubMedView ArticleGoogle Scholar
- Yang CM, Chien CS, Wang CC, Hsu YM, Chiu CT, Lin CC, Luo SF, Hsiao LD: Interleukin-1beta enhances bradykinin-induced phosphoinositide hydrolysis and Ca2+ mobilization in canine tracheal smooth-muscle cells: involvement of the Ras/Raf/mitogen-activated protein kinase (MAPK) kinase (MEK)/MAPK pathway. Biochem J 2001, 354:439–446.PubMedPubMed CentralView ArticleGoogle Scholar
- Schmidlin F, Scherrer D, Daeffler L, Bertrand C, Landry Y, Gies JP: Interleukin-1beta induces bradykinin B2 receptor gene expression through a prostanoid cyclic AMP-dependent pathway in human bronchial smooth muscle cells. Mol Pharmacol 1998, 53:1009–1015.PubMedGoogle Scholar
- Pype JL, Xu H, Schuermans M, Dupont LJ, Wuyts W, Mak JC, Barnes PJ, Demedts MG, Verleden GM: Mechanisms of interleukin 1beta-induced human airway smooth muscle hyporesponsiveness to histamine. Involvement of p38 MAPK NF-kappaB. Am J Respir Crit Care Med 2001, 163:1010–1017.PubMedView ArticleGoogle Scholar
- Parris JR, Cobban HJ, Littlejohn AF, MacEwan DJ, Nixon GF: Tumour necrosis factor-alpha activates a calcium sensitization pathway in guinea-pig bronchial smooth muscle. J Physiol 1999, 518:561–569.PubMedPubMed CentralView ArticleGoogle Scholar
- Amrani Y, Chen H, Panettieri RA: Activation of tumor necrosis factor receptor 1 in airway smooth muscle: a potential pathway th modulates bronchial hyperresponsiveness in asthma. Resp 2000, 1:1–5.View ArticleGoogle Scholar
- Hirata F, Lee JY, Sakamoto T, Nomura A, Uchida Y, Hirata A, Hasegawa S: IL-1 beta regulates the expression of the Gi2 alpha gene via lipid mediators in guinea pig tracheal muscle. Biochem Biophys Res Commun 1994, 203:1889–1896.PubMedView ArticleGoogle Scholar
- Lee JY, Uchida Y, Sakamoto T, Hirata A, Hasegawa S, Hirata F: Alteration of G protein levels in antigen-challenged guinea pigs. J Pharmacol Exp Ther 1994, 271:1713–1720.PubMedGoogle Scholar
- Hotta K, Emala CW, Hirshman CA: TNF-alpha upregulates Gialpha and Gqalpha protein expression and function in human airway smooth muscle cells. Am J Physiol 1999, 276:L405-L411.PubMedGoogle Scholar
- Amrani Y, Krymskaya V, Maki C, Panettieri RA Jr: Mechanisms underlying TNF-alpha effects on agonist-mediated calcium homeostasis in human airway smooth muscle cells. Am J Physiol 1997, 273:L1020-L1028.PubMedGoogle Scholar
- Barnes PJ: Effect of beta-agonists on inflammatory cells. J Allergy Clin Immunol 1999, 104:S10-S17.PubMedView ArticleGoogle Scholar
- Busse W: Infections. In Asthma: basic mechanisms and clinical management (Edited by: Thomson NC). London: Academic Press 1988, 483–502.Google Scholar
- Cerrina J, Le Roy Ladurie M, Labat C, Raffestin B, Bayol A, Brink C: Comparison of human bronchial muscle responses to histamine in vivo with histamine and isoproterenol agonists in vitro. Am Rev Respir Dis 1986, 134:57–61.PubMedGoogle Scholar
- Goldie RG, Spina D, Henry PJ, Lulich KM, Paterson JW: In vitro responsiveness of human asthmatic bronchus to carbachol, histamine, beta-adrenoceptor agonists and theophylline. Br J Clin Pharmacol 1986, 22:669–676.PubMedPubMed CentralView ArticleGoogle Scholar
- McGraw DW, Liggett SB: Heterogeneity in b-adrenergic receptor kinase in the lung accounts for cell-specific desensitization of the b2-adrenergic receptor. J Biol Chem 1997, 272:7338–7344.PubMedView ArticleGoogle Scholar
- Goldie RG: Receptors in asthmatic airways. Am Rev Respir Dis 1990, 141:S151-S156.PubMedView ArticleGoogle Scholar
- Barnes PJ: Neural control of human airways in health and disease. Am Rev Respir Dis 1986, 134:1289–1314.PubMedGoogle Scholar
- Paterson J, Lulich K, Goldie R: Drug effects on beta-adrenergic receptor function in asthma. in Beta-adrenoceptors in asthma. (Edited by: J Morley). Academic Press: London 1984, 245–268.Google Scholar
- Dewar JC, Wheatley AP, Venn A, Morrison JF, Britton J, Hall IP: Beta2-adrenoceptor polymorphisms are in linkage disequilibrium, but are not associated with asthma in an adult population. Clin Exp Allergy 1998, 28:442–448.PubMedView ArticleGoogle Scholar
- Israel E, et al.: Effect of polymorphism of the beta-adrenergic receptor on response to regular use of albuterol in asthma. Int Arch Allergy Immunol 2001, 124:183–186.PubMedView ArticleGoogle Scholar
- Martinez FD, Graves PE, Baldini M, Solomon S, Erickson R: Association between genetic polymorphisms of the beta2-adrenoceptor and response to albuterol in children with and without a history of wheezing. J Clin Invest 1997, 100:3184–3188.PubMedPubMed CentralView ArticleGoogle Scholar
- Israel E, et al.: The effect of polymorphisms of the beta-adrenergic receptor on the response to regular use of albuterol in asthma. Am J Respir Crit Care Med 2000, 162:75–80.PubMedView ArticleGoogle Scholar
- Chiba Y, Sakai H, Suenaga H, Kamata K, Misawa M: Enhanced Ca2+ sensitization of the bronchial smooth muscle contraction in antigen-induced airway hyperresponsive rats. Res Commun Mol Pathol Pharmacol 1999, 106:77–85.PubMedGoogle Scholar
- Kong SK, Halayko AJ, Stephens NL: Increased myosin phosphorylation in sensitized canine tracheal smooth muscle. Am J Physiol 1990, 259:L53-L56.PubMedGoogle Scholar
- Jiang H, Rao K, Halayko AJ, Liu X, Stephens NL: Ragweed sensitization-induced increase of myosin light chain kinase content in canine airway smooth muscle. Am J Respir Cell Mol Biol 1992, 7:567–573.PubMedView ArticleGoogle Scholar
- Ammit AJ, Armour CL, Black JL: Smooth-muscle myosin light-chain kinase content is increased in human sensitized airways. Am J Respir Crit Care Med 2000, 161:257–263.PubMedView ArticleGoogle Scholar
- Chiba Y, Sakai H, Misawa M: Augmented acetylcholine-induced translocation of RhoA in bronchial smooth muscle from antigen-induced airway hyperresponsive rats. Br J Pharmacol 2001, 133:886–890.PubMedPubMed CentralView ArticleGoogle Scholar
- McGraw DW, Chai SE, Hiller FC, Cornett LE: Regulation of the beta 2-adrenergic receptor and its mRNA in the rat lung by dexamethasone. Exp Lung Res 1995, 21:535–546.PubMedView ArticleGoogle Scholar
- Jacoby DB, Yost BL, Kumaravel B, Chan-Li Y, Xiao HQ, Kawashima K, Fryer AD: Glucocorticoid treatment increases inhibitory m muscarinic receptor expression and function in the airways. Am J Respir Cell Mol Biol 2001, 24:485–491.PubMedView ArticleGoogle Scholar
- Schmidlin F, Scherrer D, Landry Y, Gies JP: Glucocorticoids inhibit the bradykinin B2 receptor increase induced by interleukin-1beta in human bronchial smooth muscle cells. Eur J Pharmacol 1998, 354:R7-R8.PubMedView ArticleGoogle Scholar
- Hardy E, Farahani M, Hall IP: Regulation of histamine H1 receptor coupling by dexamethasone in human cultured airway smooth muscle. Br J Pharmacol 1996, 118:1079–1084.PubMedPubMed CentralView ArticleGoogle Scholar
- Peters SP, Fish JE: Prior use of long-acting beta-agonists: friend or foe in the emergency department? Am J Med 1999, 107:283–285.PubMedView ArticleGoogle Scholar
- Cheung D, Timmers MC, Zwinderman AH, Bel EH, Dijkman JH, Sterk PJ: Long-term effects of a long-acting beta 2-adrenoceptor agonist, salmeterol, on airway hyperresponsiveness in patients with mild asthma [see comments]. N Engl J Med 1992, 327:1198–1203.PubMedView ArticleGoogle Scholar
- Bhagat R, Kalra S, Swystun VA, Cockcroft DW: Rapid onset of tolerance to the bronchoprotective effect of salmeterol. Chest 1995, 108:1235–1239.PubMedView ArticleGoogle Scholar
- Abisheganaden J, Boushey HA: Long-acting inhaled beta 2-agonists and the loss of "bronchoprotective" efficacy. Am J Med 1998, 104:494–497.PubMedView ArticleGoogle Scholar
- Lipworth B: Tolerance with beta-agonists – a clinical problem? In Beta-2-agonists in Asthma Treatment (Edited by: Pauwels R, O'Byrne PM). New York: Marcel Decker, Inc 1997, 349–365.Google Scholar
- January B, Seibold A, Allal C, Whaley BS, Knoll BJ, Moore RH, Dickey BF, Barber R, Clark RB: Salmeterol-induced desensitization, internalization and phosphorylation of the human beta2-adrenoceptor. Br J Pharmacol 1998, 123:701–711.PubMedPubMed CentralView ArticleGoogle Scholar
- Clark RB, Allal C, Friedman J, Johnson M, Barber R: Stable activation and desensitization of beta 2-adrenergic receptor stimulation of adenylyl cyclase by salmeterol: evidence for quasi-irreversible binding to an exosite. Mol Pharmacol 1996, 49:182–189.PubMedGoogle Scholar
- Korosec M, Novak RD, Myers E, Skowronski M, McFadden ER Jr: Salmeterol does not compromise the bronchodilator response to albuterol during acute episodes of asthma. Am J Med 1999, 107:209–213.PubMedView ArticleGoogle Scholar
- Pierce KL, Luttrell LM, Lefkowitz RJ: New mechanisms in heptahelical receptor signaling to mitogen activated protein kinase cascades. Oncogene 2001, 20:1532–1539.PubMedView ArticleGoogle Scholar
- Gutkind JS: The pathways connecting G-protein coupled receptors to the nucleus through divergent mitogen-activated protein kinase cascades. J Biol Chem 1998, 273:1839–1842.PubMedView ArticleGoogle Scholar
- Yang CM, Yo YL, Hsieh JT, Ong R: 5-Hydroxytryptamine receptor-mediated phosphoinositide hydrolysis in canine cultured tracheal smooth muscle cells. Br J Pharmacol 1994, 111:777–786.PubMedPubMed CentralView ArticleGoogle Scholar
- Zacour ME, Martin JG: Enhanced growth response of airway smooth muscle in inbred rats with airway hyperresponsiveness. Am J Respir Cell Mol Biol 1996, 15:590–599.PubMedView ArticleGoogle Scholar
- Tolloczko B, Jia YL, Martin JG: Serotonin-evoked calcium transients in airway smooth muscle cells. Am J Physiol 1995, 269:L234-L240.PubMedGoogle Scholar
- Abebe W, Mustafa SJ: A1 adenosine receptor-mediated Ins(1,4,5)P3 generation in allergic rabbit airway smooth muscle. Am J Physiol 1998, 275:L990-L997.PubMedGoogle Scholar
- Nyce JW, Metzger WJ: DNA antisense therapy for asthma in an animal model. Nature 1997, 385:721–725.PubMedView ArticleGoogle Scholar
- Michoud MC, Tolloczko B, Martin JG: Effects of purine nucleotides and nucleoside on cytosolic calcium levels in rat tracheal smooth muscle cells. Am J Respir Cell Mol Biol 1997, 16:199–205.PubMedView ArticleGoogle Scholar
- Michoud MC, Tao FC, Pradhan AA, Martin JG: Mechanisms of the potentiation by adenosine of adenosine triphosphate-induced calcium release in tracheal smooth-muscle cells. Am J Respir Cell Mol Biol 1999, 21:30–36.PubMedView ArticleGoogle Scholar
- Kneussl MP, Richardson JB: Alpha-adrenergic receptors in human and canine tracheal and bronchial smooth muscle. J Appl Physiol 1978, 45:307–311.PubMedGoogle Scholar
- Noveral JP, Grunstein MM: Adrenergic receptor-mediated regulation of cultures rabbit airway smooth muscle cell regulation. Am J Physiol 1994, 267:L291-L299.PubMedGoogle Scholar
- Barnes PJ, Basbaum CB: Mapping of adrenergic receptors in the trachea by autoradiography. Exp Lung Res 1983, 5:183–192.PubMedView ArticleGoogle Scholar
- Barnes PJ, Basbaum CB, Nadel JA: Autoradiographic localization of autonomic receptors in airway smooth muscle. Marked differences between large and small airways. Am Rev Respir Dis 1983, 127:758–762.PubMedGoogle Scholar
- Zaagsma J, van der Heijden PJ, van der Schaar MW, Bank CM: Differentiation of functional adrenoceptors in human and guinea pig airways. Eur J Respir Dis Suppl 1984, 135:16–33.PubMedGoogle Scholar
- Hall IP, Widdop S, Townsend P, Daykin K: Control of cyclic AMP levels in primary cultures of human tracheal smooth muscle cells. Br J Pharmacol 1992, 107:422–428.PubMedPubMed CentralView ArticleGoogle Scholar
- Tomasic M, Boyle JP, Worley JF 3rd, Kotlikoff MI: Contractile agonists activate voltage-dependent calcium channels in airway smooth muscle cells. Am J Physiol 1992, 263:C106-C113.PubMedGoogle Scholar
- Farmer SG, Ensor JE, Burch RM: Evidence that cultured airway smooth muscle cells contain bradykinin B2 and B3 receptors. Am J Respir Cell Mol Biol 1991, 4:273–277.PubMedView ArticleGoogle Scholar
- Mak JC, Barnes PJ: Autoradiographic visualization of bradykinin receptors in human and guinea pig lung. Eur J Pharmacol 1991, 194:37–43.PubMedView ArticleGoogle Scholar
- Marsh KA, Hill SJ: Bradykinin B2 receptor-mediated phosphoinositide hydrolysis in bovine cultured tracheal smooth muscle cells. Br J Pharmacol 1992, 107:443–447.PubMedPubMed CentralView ArticleGoogle Scholar
- Pyne S, Pyne NJ: Bradykinin stimulates phospholipase D in primary cultures of guinea-pig tracheal smooth muscle. Biochem Pharmacol 1993, 45:593–603.PubMedView ArticleGoogle Scholar
- Pyne S, Pyne NJ: Bradykinin-stimulated phosphatidate and 1,2-diacylglycerol accumulation in guinea-pig airway smooth muscle: evidence for regulation 'down-stream' of phospholipases. Cell Signal 1994, 6:269–277.PubMedView ArticleGoogle Scholar
- Sarau HM, et al.: Identification, molecular cloning, expression, and characterization of a cysteinyl leukotriene receptor. Mol Pharmacol 1999, 56:657–663.PubMedGoogle Scholar
- Lynch KR, et al.: Characterization of the human cysteinyl leukotriene CysLT1 receptor. Nature 1999, 399:789–793.PubMedView ArticleGoogle Scholar
- Panettieri RA, Tan EM, Ciocca V, Luttmann MA, Leonard TB, Hay DW: Effects of LTD4 on human airway smooth muscle cell proliferation, matrix expression, and contraction in vitro: differential sensitivity to cysteinyl leukotriene receptor antagonists. Am J Respir Cell Mol Biol 1998, 19:453–461.PubMedView ArticleGoogle Scholar
- Figueroa DJ, Breyer RM, Defoe SK, Kargman S, Daugherty BL, Waldburger K, Liu Q, Clements M, Zeng Z, O'Neill GP, Jones TR, Lynch KR, Austin CP, Evans JF: Expression of the cysteinyl leukotriene 1 receptor in normal human lung and peripheral blood leukocytes. Am J Respir Crit Care Med 2001, 163:226–233.PubMedView ArticleGoogle Scholar
- Jonsson EW: Functional characterisation of receptors for cysteinyl leukotrienes in smooth muscle. Acta Physiol Scand Suppl 1998, 641:1–55.PubMedGoogle Scholar
- Hay DW, Douglas SA, Ao Z, Moesker RM, Self GJ, Rigby PJ, Luttmann MA, Goldie RG: Differential modulation of endothelin ligand-induced contraction in isolated tracheae from endothelin B (ET(B)) receptor knockout mice. Br J Pharmacol 2001, 132:1905–1915.PubMedPubMed CentralView ArticleGoogle Scholar
- Kizawa Y, Ohuchi N, Saito K, Kusama T, Murakami H: Effects of endothelin-1 and nitric oxide on proliferation of cultured guinea pig bronchial smooth muscle cells. Comp Biochem Physiol C Toxicol Pharmacol 2001, 128:495–501.PubMedView ArticleGoogle Scholar
- D'Agostino B, Gallelli L, Falciani M, Di Pierro P, Rossi F, Filippelli A: Endothelin-1 induced bronchial hyperresponsiveness in the rabbit: an ET(A) receptor-mediated phenomenon. Naunyn Schmiedebergs Arch Pharmacol 1999, 360:665–669.PubMedView ArticleGoogle Scholar
- Hay DW, Luttmann MA, Muccitelli RM, Goldie RG: Endothelin receptors and calcium translocation pathways in human airways. Naunyn Schmiedebergs Arch Pharmacol 1999, 359:404–410.PubMedView ArticleGoogle Scholar
- Takahashi T, Barnes PJ, Kawikova I, Yacoub MH, Warner TD, Belvisi MG: Contraction of human airway smooth muscle by endothelin-1 and IRL 1620: effect of bosentan. Eur J Pharmacol 1997, 324:219–222.PubMedView ArticleGoogle Scholar
- Goldie RG, Henry PJ, Knott PG, Self GJ, Luttmann MA, Hay DW: Endothelin-1 receptor density, distribution, and function in human isolated asthmatic airways. Am J Respir Crit Care Med 1995, 152:1653–1658.PubMedView ArticleGoogle Scholar
- Cerutis DR, Nogami M, Anderson JL, Churchill JD, Romberger DJ, Rennard SI, Toews ML: Lysophosphatidic acid and EGF stimulate mitogenesis in human airway smooth muscle cells. Am J Physiol 1997, 273:L10-L15.PubMedGoogle Scholar
- Nogami M, Whittle SM, Romberger DJ, Rennard SI, Toews M: Lysophosphatidic acid regulation of cyclic AMP accumulation in cultured human airway smooth muscle cells. Mol Pharmacol 1995, 48:766–773.PubMedGoogle Scholar
- Toews ML, Ustinova EE, Schultz HD: Lysophosphatidic acid enhances contractility of isolated airway smooth muscle. J Appl Physiol 1997, 83:1216–1222.PubMedGoogle Scholar
- Fortner CN, Breyer RM, Paul RJ: EP2 receptors mediate airway relaxation to substance P, ATP, and PGE2. Am J Physiol Lung Cell Mol Physiol 2001, 281:L469-L474.PubMedGoogle Scholar
- Sheller JR, Mitchell D, Meyrick B, Oates J, Breyer R: EP receptor mediates bronchodilation by PGE in mice. J Appl Physiol 2000, 88:2214–2218.PubMedGoogle Scholar
- Grandordy BM, Barnes PJ: Airway smooth muscle and disease workshop: phosphoinositide turnover. Am Rev Respir Dis 1987, 136:S17-S20.PubMedView ArticleGoogle Scholar
- Daykin K, Widdop S, Hall IP: Control of histamine induced inositol phospholipid hydrolysis in cultured human tracheal smooth muscle cells. Eur J Pharmacol 1993, 246:135–140.PubMedView ArticleGoogle Scholar
- Pascual RM, Billington CK, Hall IP, Panettieri RA, Fish JE, Peters SP, Penn RB: Comparison of chronic cytokine versus PGE2 pretreatment effects on G protein-coupled receptor (GPCR) signaling in human airway smooth muscle (HASM) [abstract]. Am J Respir Crit Care Med 2000, 161:A696.Google Scholar
- Mak JC, Barnes PJ: Autoradiographic visualization of muscarinic receptor subtypes in human and guinea pig lung. Am Rev Respir Dis 1990, 141:1559–1568.PubMedView ArticleGoogle Scholar
- Mak JC, Baraniuk JN, Barnes PJ: Localization of muscarinic receptor subtype mRNAs in human lung. Am J Respir Cell Mol Biol 1992, 7:344–348.PubMedView ArticleGoogle Scholar
- Roffel AF, Elzinga CR, Zaagsma J: Muscarinic M3 receptors mediate contraction of human central and peripheral airway smooth muscle. Pulm Pharmacol 1990, 3:47–51.PubMedView ArticleGoogle Scholar
- Roffel AF, Meurs H, Elzinga CR, Zaagsma J: Characterization of the muscarinic receptor subtype involved in phosphoinositide metabolism in bovine tracheal smooth muscle. Br J Pharmacol 1990, 99:293–296.PubMedPubMed CentralView ArticleGoogle Scholar
- Yang CM, Chou SP, Wang YY, Hsieh JT, Ong R: Muscarinic regulation of cytosolic free calcium in canine tracheal smooth muscle cells: Ca2+ requirement for phospholipase C activation. Br J Pharmacol 1993, 110:1239–1247.PubMedPubMed CentralView ArticleGoogle Scholar
- Watson N, Barnes PJ, Maclagan J: Actions of methoctramine, a muscarinic M2 receptor antagonist, on muscarinic and nicotinic cholinoceptors in guinea-pig airways in vivo and in vitro. Br J Pharmacol 1992, 105:107–112.PubMedPubMed CentralView ArticleGoogle Scholar
- Mapp CE, Miotto D, Braccioni F, Saetta M, Turato G, Maestrelli P, Krause JE, Karpitskiy V, Boyd N, Geppetti P, Fabbri LM: The distribution of neurokinin-1 and neurokinin-2 receptors in human central airways. Am J Respir Crit Care Med 2000, 161:207–215.PubMedView ArticleGoogle Scholar
- Mak JC, Astolfi M, Zhang XL, Evangelista S, Manzini S, Barnes PJ: Autoradiographic mapping of pulmonary NK1 and NK2 tachykinin receptors and changes after repeated antigen challenge in guinea pigs. Peptides 1996, 17:1389–1395.PubMedView ArticleGoogle Scholar
- Noveral JP, Grunstein MM: Tachykinin regulation of airway smooth muscle cell proliferation. Am J Physiol 1995, 269:L339-L343.PubMedGoogle Scholar
- Grandordy BM, Frossard N, Rhoden KJ, Barnes PJ: Tachykinin-induced phosphoinositide breakdown in airway smooth muscle and epithelium: relationship to contraction. Mol Pharmacol 1988, 33:515–519.PubMedGoogle Scholar
- Berger P, Perng DW, Thabrew H, Compton SJ, Cairns JA, McEuen AR, Marthan R, Tunon De Lara JM, Walls AF: Tryptase and agonists of PAR-2 induce the proliferation of human airway smooth muscle cells. J Appl Physiol 2001, 91:1372–1379.PubMedGoogle Scholar
- Berger P, Tunon-De-Lara JM, Savineau JP, Marthan R: Selected contribution: tryptase-induced PAR-2-mediated Ca(2+) signaling in human airway smooth muscle cells. J Appl Physiol 2001, 91:995–1003.PubMedGoogle Scholar
- Kawikova I, Barnes PJ, Takahashi T, Tadjkarimi S, Yacoub MH, Belvisi MG: 8-Epi-PGF2 alpha, a novel noncyclooxygenase-derived prostaglandin, constricts airways in vitro. Am J Respir Crit Care Med 1996, 153:590–596.PubMedView ArticleGoogle Scholar
- Noveral JP, Grunstein MM: Role and mechanism of thromboxane-induced proliferation of cultured airway smooth muscle cells. Am J Physiol 1992, 263:L555-L561.PubMedGoogle Scholar
- Tilley SL, Coffman TM, Koller BH: Mixed messages: modulation of inflammation and immune responses by prostaglandins and thromboxanes. J Clin Invest 2001, 108:15–23.PubMedPubMed CentralView ArticleGoogle Scholar
- Armour CL, Johnson PR, Alfredson ML, Black JL: Characterization of contractile prostanoid receptors on human airway smooth muscle. Eur J Pharmacol 1989, 165:215–222.PubMedView ArticleGoogle Scholar
- Carstairs JR, Barnes PJ: Visualization of vasoactive intestinal peptide receptors in human and guinea pig lung. J Pharmacol Exp Ther 1986, 239:249–255.PubMedGoogle Scholar
- Lazarus SC, Basbaum CB, Barnes PJ, Gold WM: cAMP immunocytochemistry provides evidence for functional VIP receptors in trachea. Am J Physiol 1986, 251:C115-C119.PubMedGoogle Scholar
- Winder SJ, Walsh MP: Smooth muscle calponin. Inhibition of actomyosin MgATPase and regulation by phosphorylation. J Biol Chem 1990, 265:10148–10155.PubMedGoogle Scholar
- Chikumi H, Vazquez-Prado J, Servitja JM, Miyazaki H, Gutkind JS: Potent Activation of RhoA by Galpha q and Gq-coupled Receptors. J Biol Chem 2002, 277:27130–27134.PubMedView ArticleGoogle Scholar
- Kim MK, Caspi RR, Nussenblatt RB, Kuwabara T, Palestine AG: Intraocular trafficking of lymphocytes in locally induced experimental autoimmune uveoretinitis (EAU). Cell Immunol 1988, 112:430–436.PubMedView ArticleGoogle Scholar
- Togashi H, Emala CW, Hall IP, Hirshman CA: Carbachol-induced actin reorganization involves Gi activation of Rho in human airway smooth muscle cells. Am J Physiol 1998, 274:L803-L809.PubMedGoogle Scholar
- Croxton TL, Lande B, Hirshman CA: Role of G proteins in agonist-induced Ca2+ sensitization of tracheal smooth muscle. Am J Physiol 1998, 275:L748-L755.PubMedGoogle Scholar
- Pang L, Knox AJ: Regulation of TNF-alpha-induced eotaxin release from cultured human airway smooth muscle cells by beta2-agonists and corticosteroids. FASEB J 2001, 15:261–269.PubMedView ArticleGoogle Scholar
- Lazzeri N, Belvisi MG, Patel HJ, Yacoub MH, Fan Chung K, Mitchell JA: Effects of prostaglandin E2 and cAMP elevating drugs on GM-CSF release by cultured human airway smooth muscle cells. Relevance to asthma therapy. Am J Respir Cell Mol Biol 2001, 24:44–48.PubMedView ArticleGoogle Scholar
- Lazzeri N, Belvisi MG, Patel HJ, Chung KF, Yacoub MH, Mitchell JA: RANTES release by human airway smooth muscle: effects of prostaglandin E and fenoterol. Eur J Pharmacol 2001, 433:231–235.PubMedView ArticleGoogle Scholar
- Gerthoffer WT: Agonist synergism in airway smooth muscle contraction. J Pharmacol Exp Ther 1996, 278:800–807.PubMedGoogle Scholar
- Ediger TL, Toews ML: Synergistic stimulation of airway smooth muscle cell mitogenesis. J Pharmacol Exp Ther 2000, 294:1076–1082.PubMedGoogle Scholar
- Togashi H, Hirshman CA, Emala CW: Qualitative immunoblot analysis of PKC isoforms expressed in airway smooth muscle. Am J Physiol 1997, 272:L603-L607.PubMedGoogle Scholar
- Hirshman CA, Togashi H, Shao D, Emala CW: Galphai-2 is required for carbachol-induced stress fiber formation in human airway smooth muscle cells. Am J Physiol 1998, 275:L911-L916.PubMedGoogle Scholar
- Fryer AD, Jacoby DB: Muscarinic receptors and control of airway smooth muscle. Am J Respir Crit Care Med 1998, 158:S154-S160.PubMedView ArticleGoogle Scholar
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