Inhibition of ADP-induced P-selectin Expression and Platelet-Leukocyte Conjugate Formation by Clopidogrel and the P2Y₁₂ Receptor Antagonist AR-C69931MX but not Aspirin

Summary

Platelet-leukocyte interactions are recognised to have pro-inflammatory effects, which may be important in the pathophysiology of ischaemic heart disease. Clopidogrel and the novel intravenous antithrombotic agent AR-C69931MX act at the level of the platelet P2Y₁₂ receptor, which is known to amplify platelet activation, aggregation and other responses induced by numerous platelet agonists. We studied the effects of clopidogrel and aspirin on ADP-induced platelet-leukocyte conjugate formation and P-selectin expression in healthy volunteers. The effects of clopidogrel and AR-C69931MX administered to patients with ischaemic heart disease were also assessed. AR-C69931MX and aspirin were also studied in vitro. Clopidogrel and AR-C69931MX suppressed ADP-induced platelet aggregation, P-selectin expression and platelet-leukocyte conjugate formation whereas aspirin had no inhibitory effect. These effects of clopidogrel and AR-C69931MX may confer therapeutic benefits in the management of acute coronary syndromes.

Keywords

Blood platelets - platelet aggregation inhibitors - adenosine diphosphate - acute coronary syndromes - leukocytes - AR-C69931MX

• References

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