Arachidonic acid-induced platelet aggregation pathway (AA-induced aggregation)

The arachidonic acid-induced platelet aggregation pathway is a critical biochemical sequence responsible for the activation and clumping of platelets during hemostasis and thrombosis. The process begins with the release of arachidonic acid from platelet membrane phospholipids by phospholipase A2, which is then converted by cyclooxygenase-1 (COX-1) into prostaglandin H2 and subsequently by thromboxane synthase into thromboxane A2 (TXA2). TXA2 acts as a potent autocrine and paracrine mediator, binding to thromboxane prostanoid (TP) receptors to trigger intracellular calcium release and platelet shape change, leading to the expression of glycoprotein IIb/IIIa receptors and definitive aggregation. This pathway is the primary target of aspirin, which irreversibly inhibits COX-1, thereby reducing TXA2 production and providing a cardioprotective antiplatelet effect. Dysregulation of this pathway is central to the pathogenesis of arterial thrombosis, myocardial infarction, and stroke.

Other names

Arachidonic acid cascade in plateletsTXA2 synthesis pathwayCyclooxygenase pathway in plateletsAA-induced platelet activation

Irreversible inhibition of cyclooxygenase-1 (COX-1) to prevent thromboxane A2 synthesis; antagonism of the thromboxane A2 (TP) receptor; inhibition of thromboxane synthase.