Effects of Vasopeptidase Inhibitor on the Expression of Myocardium Fetal Gene After Myocardial Infarction in Rats

Objective:To investigate the effects of vasopeptidase inhibitor(VPI) on ventricular remodeling,cardiac function,and expression of myocardium fetal genes after myocardial infarction(MI) in rats.Methods:Male SD rats were randomly divided into sham,MI,and MI+VPI(omapatrilat) groups.Myocardial infarction was produced by ligation of the left anterior descending coronary artery.After 24 hours of operation,rats in the MI + VPI group were treated with 40 mg/(kg·d) Omapatrilat in their drinking water,and rats in the sham and MI groups were treated with placebo.Four weeks after MI,the left ventricular hemodynamics was recorded with pressure transducer,and collagen volume fraction(CVF) and perivascular collagen volume area(PVCA) were measured with Masson staining.The fetal gene expression of myocardium fetal gene were determined with RT-PCR.Results:Four weeks after MI,the expression of αMHC mRNA of MI group were significantly decreased,and the βMHC and SKACT mRNA raised when compared with that of Sham group.The total heart weight index and relative weight of the left ventricle increased.The expression of the suppressed αMHC mRNA was upreguated,while that of βMHC and SKACT mRNA decreased by VPI after MI.The total heart weight index and the relative weight of the left ventricle in the groups of VPI lowered significantly.Conclusion:The vasopeptidase inhibitor shows favorable effects on left ventricular remodeling after MI in rats and improves cardiac function.These effects may contribute to the regulation of myocardium fetal gene expression in left ventricular.