LAUSR

AIMS Hypercholesterolemia is a hazard for increasing susceptibility of the heart to myocardial infarction (MI) by inducing platelet hyperaggregability. Clopidogrel and prasugrel have documented cardioprotective effects in clinical studies. Herein, we investigated whether clopidogrel and prasugrel could protect against isoproterenol-induced acute MI (A-MI) under hypercholesterolemic conditions in rats. MAIN METHODS Dietary hypercholesterolemic rats were subjected to acute doses of isoproterenol. Serum lipids, inflammatory markers, aortic endothelin1 and endothelial nitric oxide synthase (eNOS) mRNAs expression and immunexpression of BCL2 were determined. KEY FINDINGS Hypercholesterolemic rats showed infiltration of inflammatory cells and reduction in aortic wall thickness, deposition of fibrous tissue between cardiac muscle fibers. Protective doses of prasugrel or clopidogrel for 28 days before A-MI increased survival, amended the ECG parameters -including ST segment elevation- and improved the histopathological picture in hypercholesterolemic rats. This was coupled with reductions in platelet aggregation, creatine kinase-MB activity, endothelin 1, systemic inflammation and cardiac lipid peroxidation and increment in aortic eNOS expression. Clopidogrel and prasugrel groups showed enhanced BCL2 expression in cardiac fibers and aortic wall. SIGNIFICANCE Prasugrel and clopidogrel protected against A-MI via anti-aggregatory and anti-inflammatory effects. These results add to the value of these drugs in correcting cardiovascular dysfunction in patients vulnerable to A-MI after confirmation by appropriate human studies.