Platelet ADP receptor P2Y12 (P2Y12)

Platelet ADP receptor P2Y12 is a G protein–coupled purinergic receptor predominantly expressed on platelets and, to a lesser extent, microglia. It is activated by adenosine diphosphate (ADP) and plays a central role in platelet activation, aggregation, and thrombus formation by coupling to Gi proteins and inhibiting adenylyl cyclase, thereby lowering intracellular cAMP and increasing platelet reactivity. P2Y12 receptor blockers—both irreversible thienopyridines (clopidogrel, prasugrel, ticlopidine) and reversible inhibitors (ticagrelor, cangrelor)—are mainstays of antithrombotic therapy for cardiovascular disease. Inherited defects of P2Y12 produce mild to moderate bleeding disorders, while pharmacological inhibition is associated with increased bleeding risk but reduces major adverse cardiovascular events. The receptor also participates in inflammatory processes and has been linked to allergic asthma and cancer. Its critical regulatory role in hemostasis makes it an essential therapeutic target for preventing arterial thrombosis such as heart attack and stroke.

Other names

P2Y12 receptorP2Y12 purinoceptorPlatelet P2Y12 receptorADP receptor P2Y12P2T (historical)P2Y(cyc) (historical)SP1999 (gene/protein identifier)

Irreversible antagonism (thienopyridines: clopidogrel, ticlopidine, prasugrel); Direct and reversible inhibition (cangrelor, ticagrelor, elinogrel); Competitive binding (ticagrelor, cangrelor, elinogrel); Blockade of ADP-induced activation leading to reduced platelet aggregation and thrombus formation; Inhibition of Gi protein–mediated signaling, resulting in increased intracellular cAMP and decreased platelet activation.