Fig. 2

Role of cAMP/cGMP in imatinib-induced relaxation of GP pulmonary veins. a Effect of imatinib on intracellular cAMP. b Effect of inhibition of adenyl cyclase (SQ22536) on imatinib-induced relaxation in ET-1 (1 nM) pre-constricted PVs: (■) imatinib (n = 9); () SQ22536 (100 μM), imatinib (n = 7); (□) SQ22526 (100 μM) (n = 6). c Effect of inhibition of PKA (KT5720) on imatinib-induced relaxation in ET-1 (1 nM) pre-constricted PVs: (■) imatinib (n = 9); () KT5720 (1 μM), imatinib (n = 7); (□) KT5720 (1 μM) (n = 6). d Effect of imatinib on cGMP. e Effect of inhibition of NO-synthase (L-NAME) on imatinib-induced relaxation in ET-1 (1 nM) pre-constricted PVs: (■) imatinib (n = 9); () L-NAME (100 μM), imatinib (n = 8); (□) L-NAME (100 μM) (n = 5). f Effect of inhibition of PKG (KT5823) on imatinib-induced relaxation in ET-1 (1 nM) pre-constricted PVs: (■) imatinib (n = 9); () KT5823 (2 μM), imatinib (n = 11); (□) KT5823 (2 μM) (n = 6). A/D) Statistics was performed by the Mann–Whitney U test. b/c/e/f) Asterisks indicate different EC₅₀ values. P <0.05 are considered as significant: * p <0.05, ** p <0.01 and *** p <0.001