七氟烷后处理联合七氟烷预处理对急性心肌缺血-再灌注大鼠血浆SOD及MDA的影响

The effect of sevoflurane postconditioning combined with sevoflurane preconditioning on plasma concentrations of SOD and MDA in rats with acute myocardium ischemia reperfusion

目的探讨七氟烷后处理联合预处理是否能减轻再灌注损伤,其作用是否较单一作用更强及其机制,为临床应用提供实验依据。方法健康雄性Wistar大鼠50只,随机分为5组,假手术组(S组):大鼠冠脉只穿线不结扎;缺血再灌注组(I/R组):大鼠造模,缺血30 min,再灌注120 min;七氟烷预处理组(sevopre组):缺血前30 min,吸入2.5%的七氟烷15 min,洗脱15 min,结扎左冠状动脉前降支,再灌注120 min;七氟烷后处理组(sevopo组):大鼠再灌注前1 min吸入2.5%的七氟烷5 min,再灌注120 min;七氟烷后处理+七氟烷预处理组(pre+po组):缺血前30 min,吸入2.5%的七氟烷15 min,洗脱15 min,结扎左冠状动脉前降支,再灌注前1 min吸入2.5%的七氟烷5 min,再灌注120 min。实验结束时取颈动脉血及心肌组织分别测定丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性及心肌梗死面积。结果再灌注120 min后,pre+po组与sevopre组、sevopo组比较心肌梗死面积显著减少(P<0.05),显著升高了SOD活性,降低了丙二醛含量(P<0.05)。结论七氟烷后处理联合预处理能减少心肌梗死面积,提高再灌注后SOD活性,降低MDA含量,从而减轻心肌缺血再灌注损伤。

Objective By means of myocardial ischemia reperfusion model,to investigate whether sevoflurane postconditioning combined with sevoflurane preconditioning can reduce reperfusion injury and the protective effect is better than that of single treatment,and to explore its action mechanism in order to provide experimental basis for clinical application.Methods Fifty healthy male Wistar rats weighed 250~280g were randomly divided into 5 groups（n=10 in each group）.In anesthetized open-chest rats,the left anterior descending artery was occluded for 30 minutes and reperfused for 120 minutes.Sham operation group（group S）：placement of the silk suture under LAD without other intervention.I/R group：the rats received no other intervention except for before or after LAD occlusion.Sevoflurane preconditioning group（sevopre group）：the rats were given with 2.5% sevoflurane 30min before occlusion for 15min,and washed out for 15min,the other treatment was similar to those of I/R group;Sevoflurane postconditioning group（sevopo group）：administing 2.5 % sevoflurane 1 min before reperfusion for 5min;Sevoflurane postconditioning combined with sevoflurane preconditioning group（pre＋po group）：administrating 2.5% sevoflurane 30min before occlusion for 15min,and washed out for 15min,and administrating 2.5% sevoflurane 1min prior to reperfusion for 5min.At the end of the experiment,the carotid arterial blood and myocardium samples were got to detect myocardial infarct area,the levels of SOD and activity of MDA.Results 120min after reperfusion,infarct size（22.69±3.97） was significantly decreased（P0.05）,the superoxide dismutase（SOD） activity was markedly increased,however,MDA levels were obviously decreased（P0.05） in po ＋ pre group,as compared with those in single treatment group.Conclusion The protective effect of preconditioning combined with postconditioning with sevoflurane against myocardial ischemia reperfusion injury is probably achieved by increasing SOD activity and decreasing MDA content.