目的观察氧化苦参碱(OMT)对心肌缺血再灌注损伤中肿瘤坏死因子(TNF)、丙二醛(MDA)的含量及心肌超微结构的影响,并探讨其对心肌缺血再灌注损伤的保护作用及机制。方法结扎大鼠左冠状动脉前降支制备心肌缺血再灌注模型。雄性Wistar大鼠64只,随机分成假手术组,心肌缺血再灌注组(MIR),60和120 mg·kg^-1OMT处理组,OMT在缺血前5 min经腹腔缓慢注射。各组于缺血前,缺血30 min,再灌90,180 min检测TNF,MDA。TNF用免疫组化检测,MDA采用硫代巴比妥酸(TBA)法测定,并做电镜标本。结果①再灌注后TNF表达开始增加。再灌180 min后OMT组与同时相的MIR组比较TNF表达明显减少,而OMT 60 mg·kg^-1处理组与OMT 120 mg·kg^-1处理组相比无明显变化。②再灌注后MDA合成持续上升。OMT组再灌180 min与同时相MIR组比MDA明显减少(P<0.05),而不同剂量的OMT组之间MDA变化不显著。③电镜显示OMT能减少心肌超微结构的损伤。结论氧化苦参碱对心肌缺血再灌注损伤具有保护作用,且这种保护作用不具有剂量依赖性。

OBJECTIVE To investigate the effect of oxymatrine(OMT) on tumor necrosis factors(TNF) and malondialdehyde(MDA) during myocardial ischemic reperfusion injury in rats and its protective mechanism.METHODS Male Wistar rats were anesthetized,and the left coronary artery was ligated for 30 min and reperfused for 180 min.Sixty four male Wistar rats were divided into four groups randomly(n=16):①sham operated group;②myocardial ischemic reperfusion injury group(MIR);③60 mg·kg^-1 treated group;④120 mg·kg^-1 treated group.Rats were given oxymatrine intraperitoneally 5 min before acute ischemia and the infusion time last 5 min.TNF and MDA were measured before the occlusion of the coronary artery,30 min after ischemia and 90,180 min after reperfusion.TNF was detected by immunohistochemistry.MDA was determined by thiobarbituric acid(TBA).At 180 min after reperfusion,myocardial ischemic specimens were taken to study ultrastructure by using electron microscopy.RESULTS ①The expression of TNF was increased after reperfusion.The TNF express of OMT treated groups decreased significantly compared with MIR group after 180 min reperfusion.There was no difference in the expression of TNF between both treated groups.②A significant elevation of MDA was observed after reperfusion. Compared with MIR group,the content of MDA in OMT groups was markedly decreased(P<0.05) after 180 min reperfusion.There was no significant difference in the level of MDA between two treated groups.③Electron microscopic examination showed the pathological changes of OMT groups were ameliorated.CONCLUSION Oxymatrine protects heart from ischemic reperfusion injury in experimental ischemia reperfusion rats.And this effect is showed without a dose dependent manner.