依达拉奉对肺缺血再灌注损伤保护作用的实验研究

目的：通过建立兔在体肺热缺血再灌注模型，探讨依达拉奉对兔实验性肺缺血再灌注损伤的影响及作用机制。方法：采用兔肺原位热缺血再灌注损伤模型进行研究。24只大白兔随机分为三组：①　对照组(C组, n=8),开胸后不阻断肺门，静脉缓慢推注生理盐水5ml/kg； ②　缺血再灌注组(I/R组, n=8),左肺接受60min的缺血，然后接受60min再灌注，于缺血前5min静脉缓慢推注生理盐水5ml/kg；③　依达拉奉干预组(E组, n=8)，于缺血前5min静脉缓慢推注依达拉奉10mg/kg（5ml/kg），左肺接受60min的缺血，然后接受60min再灌注。120min实验结束时，留取各组动物血液标本,测定血浆丙二醛（MDA）含量及超氧化物歧化酶（SOD）活性；收集支气管肺泡灌洗液（BALF），检测支气管肺泡灌洗液中白细胞计数、中性粒细胞百分比及肺通透性指数；留取肺组织标本，测定肺组织湿、干重量，计算干／湿重比（D/ W）及行肺组织病理检查。结果：I/R组血浆丙二醛含量、支气管肺泡灌洗液中蛋白含量、支气管肺泡灌洗液中WBC总数及中性粒细胞百分比明显高于C组及E组（P＜0.01），E组与C组比较，无统计学意义(P＞0.05)； I/R组血浆SOD活性、血清蛋白含量及肺组织干／湿重比（D/W）较C组及E组显著降低（P＜0.05），E组与C组比较，无统计学意义(P＞0.05)；肺通透指数I/R组明显高于E组与C组（P＜0.01），E组显著高于C组（P＜0.05）；肺组织病理显示，E组肺泡内出血、炎性细胞浸润、渗出及间质水肿均较I/R组为轻。结论：依达拉奉通过清除氧自由基、抑制脂质过氧化，对兔肺原位热缺血再灌注损伤有一定保护作用。

Protection of edaravone against lung ischemia reperfusion injury in rabbits

Objective: To investigate whether or not edaravone has an effect on reducing lung ischemia-reperfusion injury in rabbits. Methods: Twenty-four rabbits were randomly divided into three groups: ① the control group(group C, n=8): received sternotomy only and no ischemia; ②　the ischemia/reperfusion group(group I/R, n=8): the left lungs of rabbits were rendered ischemia by ligating the left pulmonary hili for 60 minutes followed by 60 minutes reperfusion; ③ the edaravone group(group E, n=8): the left lungs were rendered ischemia for 60 minutes followed by 60 minutes reperfusion, and 10 mg/kg edaravone was administered intravenously 5 minutes prior to ischemia. Blood MDA and SOD were measured. Protein concentrations, WBC count, and PMN percentage in broncho-alveolar lavage fluid were determined. Samples of left lung tissue were sent for determining the left lung dry-to-wet weight ratio and evaluating the pathologic changes. Results: Blood MDA level, protein concentrations, WBC count and PMN percentage in broncho alveolar lavage fluid of group I/R were significantly higher than those of group C and group E（P＜0.01）, and there was not significant difference between group C and group E (P＞0.05); serum SOD activity, serum albumin concentration and left lung dry-to-wet ratio of of group I/R were significantly lower than those of group C and group E（P＜0.05）, and there was not significant difference between group C and group E (P＞0.05); the pulmonary permeability index of group I/R was significantly higher than that of group C and group E（P＜0.01）; pathologic evaluations revealed mild alterations in alveolar structure, less white blood cell infiltration and less interstitial edema in group E than in group I/R. Conclusions: This study suggests that intravenous edaravone prior to ischemia attenuates the lung ischemia reperfusion injury in rabbits through its radical scavenging and antioxidant action.