Figure 7

Role of Epac and PKA in basal and bradykinin-induced ERK1/2 phosphorylation. Impact of Ras-like GTPases. hTERT-airway smooth muscle cells were stimulated for the indicated period of time (A) or for 5 min without and with 100 μM 8-pCPT-2-O-Me-cAMP (8-pCPT) or 500 μM 6-Bnz-cAMP in the absence or presence of 10 μM bradykinin (10 min) (B) or 100 pg/ml Clostridium difficile toxin B-1470 or its vehicle (24 hrs) (C). Phosphorylated ERK1/2 (P-ERK1/2), total ERK1/2 or β-actin were detected by specific antibodies. Representative immunoblots are shown with the respective densitometric quantifications. Data are expressed as fold of ERK1/2 phosphorylation over unstimulated control and represent mean ± SEM of separate experiments (n = 5-7). *P < 0.05, **P < 0.01, ***P < 0.001 compared to unstimulated control; ^§ P < 0.05, ^§§ P < 0.01 compared to basal condition.