人参Rb组皂苷对犬实验性心肌梗死的保护作用

目的：研究人参Ｒb组皂苷对犬实验性心肌缺血的保护作用。方法：通过结工冠状动脉前降支（ＬＤＡ）产生急性心肌梗死模型，从心肌梗死面积（ＭＩＳ）及血清酶学变化观察人参Ｒb组皂苷的抗心肌缺血作用，并从心肌代谢及自由基损伤等角度分析其可能的作用机制。结果人参Ｒb组皂苷２５，５０mg/kg经十二指肠给药，对ＬＡＤ急悸阻断６h犬，能明显缩小ＭＩＳ，降低血清肌酸磷酸激酶（ＣＫ）及乳酸脱氢酶（ＬＤＨ）活性，亦能明显降低血清游离脂肪酸（ＦＦＡ）及过氧化脂质（ＬＰＯ）含量，提高超氧化物歧化酶（ＳＯＤ）活性。结论：人参Ｒb组皂苷对急性缺血心肌产生明显保护作用，作用机制可能与其纠正心肌缺血时ＦＦＡ代谢紊乱及对抗氧自由基引发的脂质过氧化反应，增强体内抗氧化酶活性等有关。

Protective effect of ginsenoside-Rb on experimental myocardial infarction in dogs

Object To study the protective effect of ginsenoside Rb (G Rb) on experimental dog myocardial infarction Methods Models of acute myocardial infarction were prepared by ligating the left anterior descending coronary artery of dog The anti myocardial ischemia action of G Rb was assessed by determing the changes in myocardial infarct size (MIS) and serokinases Its probable mechanism of action was proposed in view of the resultant myocardial metabolic changes and free radical injury Results The MIS in dogs pretreated with G Rb at doses of 25 mg/kg and 50 mg/kg by duodenal infusion showed a considerable reduction 6 h after coronary occlusion The activities of serum creatine phosphokinase and lactic dehydrogenase were also decreased At the same time, G Rb was found to be able to decrease the contents of free fatty acids (FFA) and lipid peroxidation products in serum, while enhancing the activity of superoxide dismutase Conclusion These findings suggested that G Rb is beneficial for myocardial ischemia, probably by modifying metabolic dysfunction of FFA, inhibiting oxygen free radical formation by peroxidation of membrane lipids and enhancing endogenous antioxidase activity