Effects of telmisartan on expressions of activin A and its receptors in non-infarction area of left ventricle in heart failure rats after myocardial infarction / 吉林大学学报(医学版)

ABSTRACT

Objective:To investigate the effects of telmisartan on the expressions of activin A and its receptors in non-infarction area of left ventricle in the heart failure rats after myocardial infarction,and to clarify the mechanism of improvement effect of telmisartan on myocardial collagen deposition.Methods:A total of 27 rats were divided into sham operation group(n=9),model group(n=20) and telmistartan group(n=10).The left anterior descending coronary arteries of the rats in model group and telmisartan groupwere ligated,and the left anterior descending coronary arteries of the rats in sham operation group were not ligated.After 5 weeks,there were 6 surviving rats in each group.The rats in sham operation group were treated with 0.5%CMC(10 mL·kg-1),the rats in model group were treated with 0.5%CMC (10 mL·kg-1),and the rats in telmisartan group were treated with telmisartan (30 mg·kg-1).All the rats were treated with medicines by intragastric administration for 4 weeks.The whole cardiac hypertrophy index and left ventricular hypertrophy index of the rats were measured;the mRNA expression levels of activin A,ActRⅡA,ActRⅡB,ColⅠ,and ColⅢ in the non-infarction areaof the rats were detected by RT-PCR and the ratio of ColⅠ/ ColⅢ was calculated;the expression intensities of activin A protein in the myocardium tissue in non-infarction area of the rats in various groups were observed by immunohistochemical staining.Results:Compared with sham operation group,the whole cardiac hypertrophy index and left ventricular hypertrophy index of the rats in model group were significantly increased (P<0.01);the mRNA expression levels of activin A,ActRⅡA and ActRⅡB,ColⅠ,ColⅢ and the ratio of ColⅠ/ColⅢ were also increased (P<0.01).The immunohistochemical staining results showed that the expression level of activin A protein in noninfarction area of left ventricle of the rats in sham operation group was lower,and the expression level of activin A protein in non-infarction area of left ventricle of the rats in model group was higher.Conclusion:Telmisartan may improve the myocardial collagen deposition by inhibiting the expressions of activin A and its receptors during heart failure.