中文摘要：

目的：探讨人参皂苷Rg1对离体大鼠心缺血/再灌注（I/R）损伤的保护作用。方法：选取SPF级SD大鼠随机分为正常对照组、I/R组、人参皂苷Rg1（1、5、10、20μmol/L）处理组。利用Langendorff灌流系统建立大鼠离体心I/R损伤模型。Lab Chart电生理系统实时监测心功能指标，血清生化检测心流出液中心肌酶含量，TTC染色法测定心肌梗死面积。结果：不同浓度人参皂苷Rg1均可改善心肌I/R损伤引起的左室发展压（LVDP）和左室内上升/下降最大速率（±dp/dtmax）的下降，并降低流出液中乳酸脱氢酶（LDH）、肌酸激酶同工酶（CK-MB）、肌红蛋白（MYO）和肌钙蛋白-I（TroI）的含量，显著减少心肌梗死面积。其中5μmol/L和10μmol/L浓度的人参皂苷Rg1对心的保护作用最显著。结论：人参皂苷Rg1具有药物预适应作用，改善心肌I/R损伤后的心肌生理功能，减少流出液中心肌酶的释放和心肌梗死面积，从而发挥抗心肌I/R损伤的保护作用。

英文摘要：

Objective： To investigate the mechanism of ginsenoside Rg1 protecting against myocardial ischemia/reperfusion （I/ R） injury in isolated rat heart. Methods： SPF Sprague Dawley rats were randomly divided into control group, I/R group, and ginsenoside Rg1 precondition group which was further divided into four sub-groups by different dosage of administration（1, 5, 10 and 20μmol/L）. Myocardial I/R injury models of isolated rat heart were established by Langendorff perfusion system. Cardiac function index was measured with Lab Chart real-time monitoring system; the content of myocardial enzymes in the outflowing liquid of the heart was measured by serum biochemical test; TTC staining method was used to determine myocardial infarct size. Results： Ginsenoside Rg1 of all the four different concentrations improved the decrease of the left ventricular developed pressure and peak systolic/diastolic left ventricular rate arising from myocardial I/R injury, and reduced the content of lactate dehydrogenase, creatine kinase;isoenzyme, myoglobin and troponin-I, thus significantly decreasing the area of cardial infarction. The 5μmol/L and 10μmol/L ginsenoside Rg1 precondition groups protected the heart most significantly. Conclusion： Ginsenoside Rg1 demonsttrates pharmacological preconditioning effect and protects against myocardial I/R injury, which improves myocardial physiological function and reduces myocardial enzyme leakage in post myocardial I/R injury, thereby reducing the myocardial infarction size.