Abstract: Objective: To investigate the effects of Mongolian new medicine-Ⅱ oncardiac functions, myocardial pathology, endoplasmic reticulum stress and myocardial apoptosis in congestive heart failure with dilated cardiomyopathy in rats.Methods: Thirty SD male rats were randomly dividedinto 3 groups(n=10):control group, dilated cardiomyopathy group (intraperitoneal injection of adriamycin 2 mg/kg body weight, 1 time/week, 4 weeks after treatment were observed for 4 weeks), Mongolian new medicine-Ⅱ group(intraperitoneal injection of adriamycin 2 mg/kg body weight, 1 time/week, 4 weeks after treatment, 30 mg/(kg·d)was given Mongolian new medicine-Ⅱ orally for 4 weeks). During the experiment, general conditions of rats were observed. After 8 weeks, these rats were killed after measurement of the cardiac function indexes by high frequency echocardiography. The morphological changes of myocardial tissues were observed by using HEstaining, VG staining and electron microscopic. The myocardial apoptosis was detected by TUNEL method and the expressions of endoplasmic reticulum chaperone GRP78, GRP94, pro-apoptotic factor CHOP and caspase-3 were monitored by Western blot. Results: ① Compared with dilated cardiomyopathy group, the cardiac systolic and diastolic functions were significantly increased in Mongolian new medicine-Ⅱ group, which were reflected in that left ventricular contraction diameter(LVIDs) and left ventricular end-diastolic diameter(LVIDd) were decreased, and left ventricular shortening fraction(FS) and ejection fraction(EF) were increased. The hemodynamic parameters of rats were improved significantly in Mongolian new medicine-Ⅱ group. ②Compared with dilated cardiomyopathy group, the myocardial lesion score was decreased and fibrosis of tissue space was relieved in Mongolian new medicine-Ⅱ group. ③Compared with dilated cardiomyopathy group, the apoptosis of myocardial cells was decreased. ④The expressions of endoplasmic reticulum chaperone GRP78, GRP94, pro-apoptotic factor chop and caspase-3 were decreased in Mongolian new medicine-Ⅱ group. Conclusion: Mongolian new medicine-Ⅱ could improve the pathologic alterations of cardiac cells and cardiac functions, decrease endoplasmic reticulum stress, the degree of fibrosis and myocardial apoptosis. The experimental results may be one of the mechanisms of treatment function of Mongolian new medicine-Ⅱ on dilated cardiomyopathy.

Key words: Mongolian new medicine-Ⅱ, dilated cardiomyopathy, endoplasmic reticulum stress, apoptosis, adriamycin, rat