Effect of carvedilol on cardiac function and left ventricular remodeling in rats after acute myocardial infarction

摘要

Objective: To observe the effect of carvedilol injection on left ventricular function and collagen remodeling in rat with myocardial infarction. Methods: Sixty rats with a model of myocardial infarction were randomly divided into nine groups. The rats of therapeutical group were treated with carvedilol injection (2 mg/d intraperitoneal injection) and/or captopil (2 g/L drinking water) . Acute myocardial infarction ( AMI) group did not receive drug treatment. The animals were sacrificed at 4 weeks and 8 weeks after coronary artery ligation. The levels of plasma angiotensin Ⅱ and plasma aldosterone and left ventricle function were determined at different time. The collagen content and the ratio of type Ⅰ and Ⅲ collagen of noninfarcted area were also assessed. Results: Compared with AMI group, the levels of plasma and myocardium angiotensin Ⅱ and plasma aldosterone in both carvedilol and captopil group decreased at the eighth week (P<0.05). In addition, carvedilol improved systolic and diastolic function (P <0.05). Compared with sham group, both collagen content and the ratio of type Ⅰ/Ⅲ collagen of noninfarcted area increased in AMI4 and AMI8 group (P <0. 05) . The hydroxyproline levels and the ratio of type Ⅰ/Ⅲ collagen significantly decreased after carvedilol and/or captopil treatment , compared with AMI group at 4 or 8 week ( P < 0.05 ). Conclusion: Carvedilol can improve cardiac function after myocardial infarction and has beneficial effect on left ventricular remodeling.