【摘要】 目的　研究西洋参叶 2 0s 原人参二醇组皂苷 (Panaxquinquefolium12 0s protopanaxdiolsaponins,PQDS)的抗实验性心肌缺血作用及其机制。方法　通过大鼠结扎左冠状动脉前降支 (LAD)产生急性心肌梗死模型 ,观察PQDS对实验性心肌梗死的影响 ,并从生化学角度探讨其作用机制。结果　ivPQDS 12 .5～ 5 0mg·kg-1,对急性心肌梗死 2 4h大鼠可明显缩小心肌梗死面积 ,降低血清CK ,LDH活性及LPO含量 ,提高SOD ,CAT及GSH Px活性 ,并能使血浆TXA2 水平明显下降 ,PGI2 /TXA2比值明显增高 ;2 5 ,5 0mg·kg-1亦可使心肌梗死及非梗死区FFA及LA含量明显降低。结论　PQDS对急性心肌缺血具有保护作用 ,可能与其增强抗氧化酶活性 ,减少自由基对心肌的氧化损伤 ,纠正心肌缺血时FFA代谢紊乱和LA堆积及PGI2 /TXA2 失衡等机制有关更多还原

【Abstract】 OBJECTIVE To study the antimyocardial ischemic effects of Panax quinquefolium 20 s protopanaxdiolsaponins (PQDS) extracted from the leaves of Panax quinquefolium and its mechanism.METHODS The changes of myocardial infarct size,the serum creatine phosphokinase(CK),lactate dehydrogenase(LDH),superoside dismutase(SOD),catalase(CAT) and glutathione peroxidase(GSH Px) activity,the serum lipid peroxidation(LPO) and myocardial free fatty acid(FFA),lactic acid(LA) content and plasma prostacycline(PGI 2) and thromboxane (TXA 2) level were determined in rats with acute myocardial infarct model induced by ligating the left anterior descending coronary artery(LAD).RESULTS After treated by PQDS(in a dosage of 12.5～50 mg·kg -1 iv at the same time of operation and 6 h later),the sizes of acute myocardial infarction were significantly reduced.The serum CK, LDH activity,the plasma TXA 2 levels and myocardial FFA and LA contents were declined,while PGI 2/TXA 2 was increased significantly.In addition,serum LPO content was declined,SOD,CAT and GSH Px levels were increased markedly.CONCLUSION PQDS had protective effect on myocardial ischemia, which may be related to improving free radicals metabolism and myocardial metabolism, decreasing plasma TXA 2 levels.Therefore,PQDS may be an effective drug for the treatment of myocardial ischemia.更多还原