Current concepts of platelet structure.

The involvement of blood platelets in hemostasis, hemorrhagic disorders, and thrombotic disease is well known. In more recent years it has been appreciated that platelets also participate in host defense against infection, transplantation rejection, would healing, and the pathogenesis of atherosclerosis. As a result, it became essential to develop knowledge of basic relationships between platelet structure, biochemistry, and function in order to define the mechanisms involved in normal hemostatic activity and pathologic behavior. The specialized approach to identify these associations has been termed platelet structural physiology and pathology. This H. P. Smith lecture summarizes relationships between platelet structure, biochemistry, and hemostatic activity and presents some of the new concepts which have resulted from the multidisciplinary approach.