Figure 4: Quercetin enhances basal cyclic AMP levels and VASP phosphorylation. Rat platelets were stirred with either the presence of vehicle or quercetin in an aggregometer, the reaction was terminated, and cAMP enzyme immunoassays and western blot for VASP activation were performed. (a) Dose-dependent quercetin effects in resting platelets cAMP levels. (b) Dose-dependent effect of quercetin on VASP activation. ((c) and (d)) Forskolin and IBMX before treatment strongly potentiated quercetin-induced platelet aggregation. Results are summary of at least 3 independent experiments performed and bar graphs presented as mean ± S.E.M. *, ** or *** versus control.