A, representative blots showing effects of acute BK treatment (1 μm, 30 s) with or without TGF‐β pre‐treatment (10 ng ml−1, 24 h) in hASMCs transfected with either ARHGEF1 siRNA, or a scrambled siRNA control, on phospho‐MYPT‐1 (Thr‐696), total MYPT1 or GAPDH as a loading control. B, data expressed as total/GAPDH show enhancement of MYPT1 protein expression by TGF‐β pre‐treatment, but no effect of ARHGEF1 siRNA or BK, ##
P < 0.01 vs. –TGF‐β. Data expressed as phospho/total (C) or phospho/GAPDH (D) show significant enhancement by both BK (*
P < 0.05, **
P < 0.01 vs. control) and TGF‐β (#
P < 0.05, ##
P < 0.01 vs. –TGF‐β) and suppression by ARHGEF1 siRNA ($
P < 0.05, $$
P < 0.01 vs. scrambled siRNA). n = 9 for all data. All comparisons by three‐way ANOVA.