Effect of ACE2 on myocardial remodeling after myocardial infarction in rat

Objective To investigate the effect of ACE2 on myocardial remodeling after myocardial infarction.Methods 32 SD rats were randomly divided into 4 group,sham-operated group(n = 8),myocardial infarction group(MI,n = 8),losartan small-dose group[MI + 10 mg /(kg·d) for 4 weeks,n = 8] and losartan high-dose group[MI +20 mg/(kg·d) for 4 weeks,n =8].Then established the myocardial infarction models,and traced the electrocardiogram in intraoperative.After 4 weeks,observing the pathological changes in myocardium by HE staining,the mRNA expression of AngⅡ and ACE2 in myocardium were detected by RT-PCR.Results Myocyte swelling,deformation and fracture were increased significantly in MI group compared with sham-operated group and were alleviated in losartan group in a dose-dependent.The mRNA expression of AngⅡ significantly upregulated in MI group than in sham-operated group,and downregulated in losartan group in a dose-dependent.The mRNA expressions of ACE2 were slightly higher in MI group than in sham-operated group and further increased in losartan group in a dose-dependent.Conclusion ACE2 can reverse myocardial remodelling by decreasing the expression of AngⅡ in losartan group.