The effect of Src family tyrosine kinase inhibition on PAC-1 binding that is induced by combined G_i and G_z stimulation. Aspirin-treated washed human platelets were stimulated for 10 minutes with the noted agonists in the presence of FITC-labeled PAC-1 mAb. Samples were diluted with Tyrode buffer and analyzed on a flow cytometer for increases in fluorescence that are correlated with GPIIb/IIIa activation. Data were calculated as mean fluorescence of the total platelet population. Each bar is the average of 3 experiments ± SE from 3 donors. Single asterisk (*) denotes P < .05 compared to unstimulated. Double asterisk (**) denotes P < .05 when compared to single asterisk samples.