20（S）-人参皂苷Rg3抗异丙肾上腺素诱导心肌缺血作用

目的]研究20（S）-人参皂苷Rg3抗心肌缺血作用及其机制.方法]随机将50只Wistar大鼠分成5组,即空白对照组（CON）,异丙肾上腺素组（ISO）,20（S）-人参皂苷Rg3（5、10、20 mg/kg）组.各组大鼠灌胃给予相应药物,除CON外其余各组大鼠皮下注射盐酸异丙肾上腺素（20 mg/kg）制备心肌缺血模型.末次注射异丙肾上腺素2h后麻醉大鼠,取血检测血清中肌酸激酶（creatine kinase,CK-MB）和乳酸脱氢酶（lactate dehydrogenase,LDH）活力,取大鼠左心室制备匀浆后检测心肌组织超氧化物歧化酶（superoxide dismutase,SOD）活性、谷胱甘肽过氧化物酶（glutathione peroxidas,GSH-Px）活性、总抗氧化能力（total antioxygencapabilit,T-AOC）及丙二醛（malonaldehyd,MDA）含量.结果]与CON组相比,ISO组血清CK-MB、LDH活力明显增高.与ISO组比较,20（S）-人参皂苷Rg3（5,10,20 mg/kg）可显著降低血清CK-MB、LDH活力；与CON组比较,ISO组SOD活性、GSH-Px活性及T-AOC降低,MDA含量增高；与ISO组相比,20（S）-人参皂苷Rg3（5、10、20 mg/kg）可显著提高SOD活性、GSH-Px活性及T-AOC,降低MDA含量.结论]20（S）-人参皂苷Rg3具有抗心肌缺血作用,其作用机制与清除自由基和抗脂质过氧化有关.

Effects of 20(S)-ginsenoside Rg3 on myocardial ischemia induced by isoproterenol

Objective] This study aims to investigate the effects and mechanism of 20（S）-ginsenoside Rg3 on myocardial ischemia. Methods ] 50 Wistar rats were random divided into 5 groups that include the blank control group（CON） ,Isoprenaline group（ISO）, 20 （S）-ginsenoside Rg3 groups （.5,10, 20 mg/kg）.The drugs were administered by orally. All rats, except those in the control group, were subcutaneously injected with isoproterenol （20 mg/kg） to induce myocardial ischemia. Two hours after the last isoproterenol injection, the rats were anaesthetized and sacrificed. The activities of creatine kinase （CK-MB）, lactate dehydrogenase （LDH） in serum and superoxide dismutase （SOD） , glutathione peroxidase （GSH-Px） in heart tissues left ventricle homogenate were assayed. The total antioxidant capacity （T-AOC） and the malondialdehyde （MDA） content were assayed also. Results ] Comparing with the control group, the activities of CK-MB and LDH were increased significantly in ISO group. Comparing with ISO group, 20（S）-ginsenoside Rg3 （5, 10, 20 mg/kg） resulted in a reduction in CK-MB and LDH significantly. Comparing with the control group, the activities of SOD, GSH-Px and T-AOC were decreased in ISO group, the content of MDA were increased. 20（S）-ginsenoside Rg3 （5, I0,20 mg/kg） inhibited not only the elevation of MDA content but also the reduction of the activities of SOD, GSH-Px and T-AOC. Conclusions] The present findings suggest that 20（S）-ginsenoside Rg3 exerted cardioprotective effects against myocardial ischemic injury. The mechanism of action concerned with free radicals scavenging and anti-lipid peroxidation.