Soluble FITC-fibrinogen binding to platelets activated by ADP, Par4 receptor-activating peptide, or convulxin. Platelets were stimulated with varying concentrations of agonist, and the binding of soluble FITC-fibrinogen to platelets was determined by flow cytometry. ADAP^+/+ or ADAP^−/− platelets stimulated with (A) ADP, (B) Par4, or (C) convulxin. Results are shown as the percentage of ADAP^+/+ FITC-fibrinogen binding to ADAP^+/+ cells for a given agonist concentration ± SEM (*P < .05; **P < .01). Results are a summary of at least 4 separate experiments.