[Protective effects of Leonurus japonicas on myocardial remodeling induced by isoproterenol in rats]
Chen Zhang1, Yan-Pin Gu, Bao-Ping Yuan
1Department of Pathology, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China. pathofshutcm@yahoo.com.cn
Objective:
To investigate the effects of Leonurus japonicas on myocardial remodeling induced by isoproterenol (ISO) in rats.
Methods:
The model of rat myocardial remodeling was established by subcutaneous injection of ISO (20,10 and 5 mg/kg for 3 days, subsequently 3 mg/kg for 7 days). Rats were randomly divided into five groups: Control, ISO, ISO + enalapril, ISO + Leonurus 8 g/ kg and ISO + Leonurus 16 g/kg. Recorded the values of LVSP, LVEDP, +/- dp/dt (max), cardiac output ( CO). Weighed the body weight (BW), heart weight (HW) and left ventricular weight (LVW) of rats to calculate the values of HW/BW and LVW/BW. The hydroxyproline contents were investigated by spectrophotometric measurement. The contents of type I collagen and type III collagen and ratio of I/III collagen were assessed by immunohistochemical stain.
Results:
Leonurus (16 g/kg x day(-1)) could increased the value of LVSP, + dp/dt(max), CO (P < 0.05). Leonurus (8 g/kg) could increased the value of -dp/dt(max), decreased the ratios of HW/BW and LVW/BW (P < 0.05), the contents of hydroxyproline, type I collagen, type III collagen and the ratios of I/III collagen (P < 0.05).
Conclusions:
Leonurus at a dosage of 16 g/kg may improve the systolic function; Leonurus at a dosage of 8 g/kg may improve the diastolic function, down-regulate the expression of collagen and normalize the ratio of I/III collagen.
