Clopidogrel's antiplatelet effect lasts for the life of the platelets because it irreversibly inhibits which receptor?

Clopidogrel's antiplatelet effect lasts for the life of the platelets because it irreversibly inhibits which receptor?

• A. P2Y12
• B. GP IIb/IIIa
• C. PAR-1
• D. TXA2 receptor

Answer: (B)

Clopidogrel provides its antiplatelet effect by irreversibly inhibiting the P2Y12 ADP receptor on platelets. The active metabolite forms a covalent bond with this receptor, so once blocked, a platelet cannot participate in ADP-induced aggregation for its entire lifespan. Platelets are anucleate and cannot synthesize new receptors, so the effect lasts until new platelets are produced, typically about 7 to 10 days. The receptor targeted by clopidogrel is P2Y12; GP IIb/IIIa is blocked by other drugs, PAR-1 by different agents, and the TXA2 receptor is not the direct target of clopidogrel (though aspirin affects TXA2 production).

Clopidogrel provides its antiplatelet effect by irreversibly inhibiting the P2Y12 ADP receptor on platelets. The active metabolite forms a covalent bond with this receptor, so once blocked, a platelet cannot participate in ADP-induced aggregation for its entire lifespan. Platelets are anucleate and cannot synthesize new receptors, so the effect lasts until new platelets are produced, typically about 7 to 10 days. The receptor targeted by clopidogrel is P2Y12; GP IIb/IIIa is blocked by other drugs, PAR-1 by different agents, and the TXA2 receptor is not the direct target of clopidogrel (though aspirin affects TXA2 production).