Fig. 3. Inhibitory effects of propofol on strain-increased extracellular signal-regulated kinases (ERK) phosphorylation. (  A ) Effect of propofol (1–30 μm) on strain-activated ERK phosphorylation. (  B ) Effect of propofol on strain- or H²O²-induced phosphorylation of ERK. Human umbilical vein endothelial cells (HUVECs) were incubated with either propofol (30 μm) or antioxidant Trolox (200 μm) and stimulated with cyclic strain or H²O²(25 μm) for 30 min. Data are represented as fold increase relative to control groups. The results show mean ± SEM (n = 6). *  P < 0.05  versus control; #  P < 0.05  versus strain (or H²O²) alone (analysis of variance [ANOVA]).