Defective ERK and p38 phosphorylation are responsible for impaired platelet aggregation of MINK1^−/− platelets. (A,C,E,G) Aggregation and ATP release of WT or MINK1^−/− platelets stimulated with collagen (0.8 μg/mL) or thrombin (0.025 U/mL) incubated in the presence of dimethylsulfoxide (DMSO), U0126 (10 μM), or SB203580 (10 μM) for 5 minutes. (B,D,F,H) The bar chart shows means ± SEM of the percentage of platelet aggregation and ATP release from at least 3 independent experiments depicted in panels A, C, E, and G (*P < .05, **P < .01 between WT and MINK1^−/− mice, paired Student t test).