依达拉奉对离体大鼠心肌缺血再灌注损伤的保护作用

目的:探讨依达拉奉(ED)预先给药对大鼠离体心肌缺血再灌注(I/R)损伤的作用及其机制。方法:制作Langendorff主动脉逆行灌注心脏I/R模型。24只雄性大鼠随机分为三组(n均=8):对照组(C组)、I/R组、ED组。观察各组大鼠I/R后心功能指标:左室收缩峰压(LVSP)、左室压上升最大速率(+dp/dtmax)、左室压下降最大速率(-dp/dtmax)、冠脉流量(CF)、心肌细胞乳酸脱氢酶(LDH)及肌酸激酶同工酶(CK-MB)活性、心肌组织丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性。结果:与基础值和C组比较,I/R组再灌注时各时点的CF、LVSP、+dp/dtmax、-dp/dtmax降低(P<0.05);与I/R组比较,ED组再灌各时点的CF、LVSP、+dp/dtmax、-dp/dtmax增高(P<0.05);ED组心肌SOD活性明显高于I/R组(P<0.05),LDH及CK-MB活性、MDA含量低于I/R组(P<0.05)。结论:ED对I/R心肌有保护作用,能促进心功能恢复。其机制与清除自由基和减轻氧化应激有关。

The Protective Effects of Edaravone on Myocardial Ischemia-Reperfusion Injury to Isolated Rat Heart

Objective:To investigate the cardioprotective effects of edaravone(ED) on ischemia/reperfusion(I/R) myocardium and its potential underlying mechanism in isolated rat heart. Method: Langendorff perfusion was used to induce the heart I/R injury. Twenty-four male Sprague-Dawley(SD) rats were randomly divided into 3 groups(n=8,respectively):control(C) group,I/R group,ED group.Left ventricular systolic pressure(LVSP),±dp/dtmax,coronary flow(CF) were monitored before ischemia and at 10,30 and 60 min of reperfusion. At the end of 60 min reperfusion,CF was collected for determination of CK-MB and LDH activity,and the hearts were removed for determination of myocardial MDA content and SOD activity. Results: The level of LVSP,±dp/dtmax,CF in the period of reperfusion were lower than the baseline level only in I/R group(P<0.05). While in the period of reperfusion,the indexes of cardiac function including LVSP,±dp/dtmax and CF in ED group were significantly better than I/R group(P<0.05). In the same time,SOD activity were much better preserved in ED group,and the level of CK-MB,LDH and MDA content were lower in ED group than I/R group(P<0.05). Conclusion: ED can promote the recorvery of cardiac function in the isolated rat heart and protect myocardium from I/R injury by scavenging free radical and reducing oxidative stress.