Effects of treating with carvedilol on left ventricular remodeling following acute myocardial infarction in rats

Objective To observe the pathologic variation of left ventricular remodeling in myocardial tissue following AMI by earlier treating with carvedilol in rats.Methods Sixty Wistar rats were randomly divided into sham group,AMI group,low dose carvedilol group and high dose carvedilol group.Rats were administrated carvedilol of 1 mg ·(kg · d)-1 and 2 mg ·(kg · d)-1 following AMI in low dose and high dose carvedilol group.The echocardiography examination was done at 1 day before operation and 2 weeks after operation.The level of BNP in serum was detected by ELISA.After the hearts were harvested at 2 weeks after ligation,histopathological sections and immunohistochemistry of CD31,CD34,bcl-xl and Bax expression were carried out.Results After the administration of carvedilol,the volume of LVESD,LVEDD,IVS and HR were reduced and that of EF was increased and BNP in serum decreased significantly in carvedilol groups compared with AMI group(P0.05).The expression of CD31,CD34 and bcl-xl increased in both carvedilol groups,while the expression of bax decreased in both carvedilol groups.The area of infarction reduced and residual myocardial increased in infarction region in both carvedilol groups.The high dose carvedilol group was better than the low dose carvedilol group.Conclusions The earlier administration of carvedilol to AMI rats can improve cardiac function and prevent left ventricular remodeling.