Figure 1: Quercetin inhibits agonist-induced platelet aggregation. Platelets were preincubated with quercetin in the presence of 1 mM CaCl2 for 2 min at 37°C and stimulated with collagen (a), ADP (b), and thrombin (c). Aggregation was terminated at 5 min and percent aggregation was determined. Tracings ((a), (b), and (c)) are summary of 8 to 10 experiments with mean ± SEM of at least 8 independent experiments. * , ** or *** versus agonist activated control.