Role of the platelet in atherogenesis.

Studies thus far have shown that arterial endothelial desquamation produced by mechanical injury with a balloon catheter or chemical injury from chronic homocystinemia or hypercholesterolemia elicits a sequence of events that includes platelet adherence, aggregation, and release at the sites of exposed subendothelial connective tissue, followed by smooth muscle cell migration and proliferation in the intima of the injured segments of the artery wall. During the release reaction, platelets provide a mitogen, not present in plasma, that is important in promoting the proliferative response of smooth muscle cells that results in the formation of atherosclerotic lesions. Studies in primates and platelet survival studies in man suggest a possible therapeutic role for some antiplatelet drugs in the pharmacologic inhibition of atherogenesis.