[Coagulation/fibrinolytic system and platelet in acute coronary syndrome].

Coagulation/fibrinolytic system and platelet function play roles not only in the onset of acute coronary syndrome (ACS) but also in the development of atherosclerosis, which is a major underlying condition of ACS. In this paper we reviewed the involvement of coagulation/fibrinolytic system and platelet in coronary atherosclerosis and ACS. It is well known that hyperchoresterolemia and diabetes mellitus (DM) are the important risk factor for coronary atherosclerosis and ACS. Both oxidized LDL and advanced glycation endproduct (AGE) activate endothelial cells with down-regulating thrombomodulin and tissue plasminogen activator(t-PA) expression. Moreover the oxidized LDL and AGE up-regulate the expression of tissue factor, and t-PA inhibitor, PAI-1. Thus Ox-LDL and AGE impair the endothelial antithrombotic function and result ACS. These may explain the pathomechanism of coronary sclerosis and ACS. In the atherosclerotic lesion with narrowing the lumen, high shear stress may be occurred. Recent observations suggested that high shear stress induces platelets aggregation named as shear stress induced platelet aggregation (SIPA), which may also have very important role for the pathogenesis in ACS.