Effects of valsartan on left ventricular collagen remodeling in rat models with myocardial infarction

Objective To investigate the effects of valsartan on experimental left ventricular collagen remodeling (LVRM) in rats with myocardial infarction (MI). Methods Ligate anterior descending branches of coronary artery of Sprague-Dawley rats were used to establish models of acute myocardial infarction (AMI). Seventy rats were randomly divided into 6 groups:①Sham groups:including Sham 1(n=5) and Sham 4(n=5).The pericardium of rats in Sham groups were cut open and sutured immediately. The rats were routinely breeded for 1 week and 4 weeks,respectively, 1.5 mL saline was poured into stomach of rats once a day;②Control groups:AMI 1 (n=10) and AMI 4 (n=10). 1.5 mL saline was poured into stomach of rats with AMI once a day for 1 week and 4 weeks,respectively;③Valsartan groups:VAS1 (n=10) and VAS 4 (n=10). Valsartan of the dosage of 10 mg·kg -1·d -1 and 1.5 mL saline were poured into stomach of rats with AMI for 1 week and 4 weeks(once a day),respectively. The ratio of collagen type Ⅰ to Ⅲ in non-infarction myocardium in left ventricle was detected by immunohistochemical method. The levels of Ang Ⅱ, aldosterone (ALD), endothelin (ET), thromboxane A 2 (TXA 2), and prostacyclin I 2 (PGI 2) in plasma were measured by radioimmunoassay. Results ①The ratio of collagen type Ⅰ to Ⅲ in non-infarction myocardium in left ventricular was decreased;②Compared with control groups, valsartan could decrease ALD, ET, and TXA 2 and increase AngⅡ and PGI 2 in plasma. Conclusion Valsartan has beneficial effects on LVRM after MI.