“渐处理”对肺缺血再灌注损伤的保护作用

Gradual reperfusion protects against ischemia/reperfusion lung injury in rats

目的探讨"渐处理"作为一种改良的后处理方式对大鼠肺缺血再灌注损伤的保护作用及其机制。方法采用大鼠肺原位缺血再灌注损伤模型进行研究。将40只清洁级SD大鼠随机分为四组:手术对照组(S组),缺血再灌注组(I/R组),缺血后处理组(IPO组),缺血后渐处理组(IGR组)。观察肺组织病理形态变化,测定肺组织湿/干重比(W/D),检测肺组织匀浆中丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性。结果与S组比较,I/R组光镜下见肺组织病变明显加重,肺组织W/D明显增加,肺组织中SOD活力明显降低,MDA的浓度明显增高(P<0.01);与I/R组比较,IPO组及IGR组肺组织病变减轻,肺组织W/D明显降低,肺组织中SOD活力明显升高,MDA的浓度明显降低(P<0.01);IGR组与IPO组比较,上述各项指标均有所减轻,两者差异无统计学意义(P>0.05)。结论 "渐处理"对大鼠肺原位缺血再灌注损伤有保护作用。与缺血后处理比较,是一种更有效的、更适合临床应用的、减轻再灌注损伤的方法。

Objective To explore protective function and mechanism of gradual reperfusion,a modified ischemic postconditioning,on ischemia-reperfusion lung injury in rats.Methods The study was performed on a reliable extracorporeal rat lung ischemia-reperfusion injury model.Forty rats were randomly divided into four groups： the sham group（S group）,the ischemic reperfusion group（I/R group）,ischemic postconditioning group（IPO group）,and gradual reperfusion group（IGR group）.Lung tissue histological changes were examined;the ratio of lung wet weight to dry weight（W/D） was evaluated;malondialdehyde（MDA） content and activities of superoxide dismutase（SOD） in lung tissues were measured.Results Compared with S group,the obvious pathologic changes（including lung edema,hemorrhage,and inflammatory cells sequestration） and the W/D ratio were significantly increased in I/R group,lung tissue SOD activity were significantly decreased,while the concentration of MDA were significantly increased（P 0.01）.Compared with the I/R group,the pathologic changes and the W/D ratio in the IPO and IGR group were significantly decreased,lung tissue SOD activity was significantly increased,while the concentration of MDA was significantly decreased（P 0.01）;and the effects were especially obvious in IGR group rats,however,there were no significant difference between IPO and IGR group（P 0.05）.Conclusion Gradual reperfusion has obvious protective effects on ischemia-reperfusion lung injury in rats,and can be a more effective and suitable method for clinical application to reduce reperfusion injury.