FIGURE 5.

ADP partially restores aggregation response but not Syk Tyr-525/526 hyperphosphorylation in the presence of PKC inhibition. A, representative aggregation tracings of human platelets stimulated with 200 ng/ml Cvx in the absence and presence of the pan-PKC inhibitor GFX (5 μm). In some cases, samples were concomitantly stimulated with 200 ng/ml Cvx and 10 μm ADP. B, analyzed for Syk phosphotyrosine 526/526 and total Syk. C, quantitation of the blots with mean ± S.E. (error bars) of relative Syk phosphorylation for Cvx in untreated (●), GFX treated (■) and GFX with exogenous ADP addition (▴) platelets plotted against time. Student's t test was performed (p < 0.05, untreated versus GFX-treated platelets, and no significant difference was observed between GFX-treated platelets versus GFX+ADP added platelets). Blots are representative of at least three independent experiments.