Figure 3. The effects of Rho-kinase inhibitors and the removal of extracellular Ca²⁺ on the thrombin-induced MLC phosphorylation and decrease in the TEER in PAECs.

(a) The concentration-dependent effects of Y27632 (0.01–10 μM; n = 4–6) and H1152 (0.01–1 μM; n = 4) on pMLC and ppMLC 3 min after stimulation with 1 u ml⁻¹ thrombin (Control: n = 10). The control values were those obtained 3 min after thrombin stimulation in the absence of inhibitors. (b) The temporal changes in pMLC and ppMLC (n = 4) and the TEER (n = 6 for control; n = 5 for Y27632; n = 4 for H1152) after stimulation with 1 u ml⁻¹ thrombin in the absence and presence of 10 μM Y27632 or 1 μM H1152. (c) The temporal changes in pMLC and ppMLC (n = 4) and the TEER (n = 5) after stimulation with 1 u ml⁻¹ thrombin in the presence and absence of extracellular Ca²⁺. PAECs were exposed to Y27632, H1152 or Ca²⁺-free HBS 30 min prior to and during thrombin stimulation. The data are the means ± SEM. *P < 0.05 vs. control, according to an ANOVA followed by Dunnett’s post-hoc test.