Figure 5.

Calcium mobilization and tyrosine kinase signaling are unaffected in endobrevin/VAMP-8^−/− platelets. (A) Wild-type (WT, black traces) and VAMP-8^−/− platelets (V8^−/−, gray traces) were prepared, and intracellular free calcium levels were measured with Fura-2. The arrows indicate the times at which extracellular calcium and thrombin were added. Each trace represents the average of three. (B) WT or VAMP-8^−/− platelets were incubated with the indicated agonist for 2 min at RT. The reactions were stopped and the samples were analyzed by Western blotting using an anti-phosphotyrosine antibody.