Effect of BAPTA-AM on the inhibition by HA1077 and Y-27632 on thrombin (0.1 U/mL)-induced MLC phosphorylation in intact platelets. Platelets pretreated with vehicle (□) or 7.5 μmol/L BAPTA-AM (▪) for 3 minutes were treated with 20 μmol/L HA1077 or 10 μmol/L Y-27632 for 5 minutes. Platelets were stimulated with 0.1 U/mL thrombin for 20 seconds without stirring, and MLC phosphorylation was analyzed, as described for Fig 3. Data represent the mean ± SE of three experiments. *P < .05, **P < .01.