P-selectin,also known as GMP140 or CD62P,is a transmembrane glycoprotein that mediates the interaction of activated endothelial cells or platelets with leukocytes. It is an adhesion molecule involved in the pathogenesis of inflammation,thrombosis,and oncogenesis. P-selectin is stored in the alpha-granules of platelets and Weibel-Palade bodies of endothelial cells. Upon cell activation by agonists,P-selectin is transported rapidly to the cell surface.