Pink J: Effect of propranolol on platelet function

Excessive reactivity of blood platelets may contribute to atherosclerotic vascular dis-ease. Hence drugs which alter platelet function may be protective. Prompted by findings that propranolol therapy normal-ized hyperactive platelet aggregation in patients with coronary artery disease, we studied propranolol in vitro to assess its action on platelets. At concentrations sim-ilar to those achieved in vivo (0.1-1 jiM), propranolol raised the thresholds for ag-gregation of some normal platelets by adenosine diphosphate (ADP). At higher concentrations (10-50 jiM), propranolol abolished the second wave of platelet ag