Effect of miR-21 on MHC-α mRNA expression on junctional zone post acute myocardial

Objective:To detect the effect of miR-21 on MHC-αmRNA expression in myocardium post acute myocardium infarction in rat.Method:Rats underwent left descending coronary ligation or sham surgery.Rats with MI were assigned in two groups(n=8).Real-time PCR was used to detect the expressions of miR-21,MHC-α and MHC-βmRNA.MHC-αand MHC-βprotein was tested by IHC,in myocardium.Result:The expression level of miR-21in myocardium was up-regulated in the 14th and 28th day post MI.Compared to sham group,the expression level of miR-21in myocardium was increased by 34%(P0.01)in the 14th day and by 89%(P 0.01)in the 28th day post MI.The expression levels of MHC-α,MHC-βmRNA were altered in the progress of ventricular remodeling post MI in rat.The expression level of MHC-αmRNA in myocardium was decreased by 44%(P0.01)in the 14th day and by 68%(P0.01)in the 28th day post MI.The expression level of MHC-βmRNA in myocardium was increased by 2.16fold(P0.01)in the 14th day and by 3.62fold(P0.01)in the 28th day post MI.Conclusion:The expression levels of miR-21and MHC-αwere altered in the progress of ventricular remodeling post MI in rat.miR-21might be involved in ventricular remodeling post MI.