黄芪中不同提取成分对在体大鼠心肌缺血-再灌注损伤的心功能影响

目的 :观察黄芪中不同提取成分对心肌缺血 再灌注损伤大鼠心功能的影响。方法 :通过结扎大鼠左室冠状动脉前降支造成心肌缺血 再灌注损伤模型 ,观察静脉内注射黄芪中不同提取成分对心肌缺血 再灌注损伤过程中血流动力学和缺血心肌Na⁺ K⁺ ATP酶活性、cAMP和丙二醛含量的影响。结果 :黄芪甲甙、总皂甙和总黄酮能够减轻心肌缺血 再灌注引起的左心室内压、左心室内压最大上升与下降速率振幅的下降 ;并能使缺血心肌组织中Na⁺ ,K⁺ ATP酶活性降低。另外 ,黄芪总皂甙能够增加缺血心肌组织中cAMP含量 ;黄芪总黄酮能够降低缺血心肌组织中丙二醛的含量。结论 :黄芪中不同提取成分对大鼠心肌缺血 再灌注引起心功能损害具有保护作用 ,其机制可能涉及到能量代谢的改善或自由基生成的抑制和氧自由基的清除。

Effects of Components Isolated from Astragalus membranaceus Bunge on Cardiac Function Injured by Myocardial Ischemia Reperfusion in Rats

Objective: To investigate the effects of components isolated from Astragalus membranaceus on myocardial ischemia reperfusion injury. Methods: The myocardial ischemia reperfusion injury model was created by the left anterior descending coronary artery occlusion from the oracotouated rats, and the total saponins, total flavonids and astragaloside IV isolated from A. membranaceus on hemodynamics during acute myocardial ischemia ,Na⁺-K⁺-ATPase activity, cAMP and malondialdehyede (MDA) contents in the ischemic myocardium were observed Results: The total saponins, total flavonids and astragaloside IV attenuated the declines of the amplitudes of LVSP and ±LVdp/dt_max in rat heart injured by ischemia reperfusion in vivo, and decreased Na⁺-K⁺-ATPase activity in the ischemic myocardium. Otherwise, the total saponins increased the cAMP content and the total flavonids decreased the level of MDA production in the ischemic myocardium. Conclusion: The effects of different components isolated from A. membranaceus on protecting the cardiac function in the process of ischemia reperfusion may be related to the mechanism of improving energy metabolism, scavenging the oxygen free radicals and inhibiting the production of free radicals in the ischemic myocardium.