Protective effects of DLXSS on ischemia/reperfusion injury in isolated rat hearts
GAO Qi;HUANG Wendong;SU Meiling;YANG Yongfei;ZENG Zhi;ZHU Banghao;Cardiac and Cerebral Vascular Center, Zhongshan School of Medicine, Sun Yat-Sen University;
Objective: To investigate the protective effect of Danlingxinshu capsule(DLXSS) on myocardial ischemia/reperfusion(I/R) injury in isolated rat hearts and its underlying mechanisms. Methods: Thirty-five SD rats were divided into five groups randomly(n=7): normal group; model group; DLXSS high, middle, low dose groups(96, 32, 11 mg/kg). Drug groups were gave DLXSS by intragastric administration once a day for 7 days consecutively, meanwhile the normal and model groups were administered with normal saline. A total of 60 min after last perfusion, the hearts were separated and perfused with Krebs-Henseleit(K-H) buffer solution on Langendorff apparatus. Hearts were in equilibrium for 20 min, then after 20 min of global ischemia, then were reperfused for 60 min. The normal group was perfused for 100 min consecutively. Myocardial hemodynamic parameters were monitored and recorded, such as left ventricular systolic pressure(LVSP), left ventricular developed pressure(LVDP), heart rate(HR), the maximum change rate of ventricular pressure rise and fall(±dp/dtMax). At the same time, coronary effluent was collected and biochemical parameters, such as lactate dehydrogenase(LDH), creatine kinase(CK), superoxide dismutase(SOD), malondialdehyde(MDA) in coronary effluent were measured as well. Histopathological examination of left ventricle was performed. Results: Compared with model group, administration of DLXSS significantly reduced myocardial injury and ameliorated heart function, with the increase in left ventricular systolic pressure, the maximum change rate of ventricular pressure rise and fall(±dp/dtMax)(P0.05 or P0.01), and activities of LDH, CK, in effluent samples of DLXSS groups were lower than those in I/R group(P0.05 or P0.01), SOD activities was lower than that in I/R group, MDA content was obviously lower than the I/R group(P0.05 or P0.01). Histopathological examination showed that DLXSS also could ameliorate myocardial injury and heart function inordinately. Conclusion: Our results showed that DLXSS pretreatment can protect the cardiac function from the injury caused by ischemia/reperfusion, and the mechanism of pharmacological action might be related to the antioxidative activity of DLXSS.