异氟醚对大鼠肺缺血-再灌注损伤的影响

Effects of isoflurane administration before ischemia on lung ischemia-reperfusion injury in rats

目的探讨异氟醚对大鼠肺缺血-再灌注损伤的影响。方法建立在体大鼠肺缺血-再灌注模型。120只SD雄性大鼠,随机分成四组:缺血-再灌注组(IR组),异氟醚-缺血-再灌注组(ISO-IR组),异氟醚组(ISO-C组)和手术对照组(C组),每组30只。分别在缺血45 min、再灌注30、60、120 min处死大鼠行动脉血气分析、肺组织湿干比(W/D)值、丙二醛(MDA)含量及髓过氧化物酶(MPO)活性测定和肺组织病理学检查;此外,各组于再灌注120 min时另处死大鼠行支气管肺泡灌洗,取灌洗液(BALF)行白细胞计数、沉渣白细胞分类和BALF中总蛋白(TP)含量测定。结果再灌注后,IR组和ISO-IR组肺组织W/D值、MDA含量和MPO活性逐渐升高,且显著高于C组(P<0.05);但再灌注60 min后,ISO-IR组肺组织W/D值、MDA含量和MPO活性较IR组均有所降低(P<0.05)。IR组BALF中的中性粒细胞(PMN)所占百分比较C组显著升高(P<0.05),而ISO-IR组的升高并不显著但较IR组显著降低;IR组和ISO-IR组BALF中TP含量均较C组显著升高(P<0.05),但ISO-IR组又低于IR组(P<0.05);肺组织病理学检查示ISO-IR组病理学变化较IR组显著减轻。结论异氟醚的吸入对缺血-再灌注损伤的肺组织具有一定的保护作用。

Objective To investigate the effect of isoflurane administration before ischemia on lung ischemia-reperfusion injury in rats. Methods The ischemia rat model with occlusion of left pulmonary hilum for 45 min was used in this experiment. One hundred and twenty male SD rats were randomly divided into four groups with 30 rats each. Interruption of perfusion and ventilation for 45 rain followed by reperfusion in group IR, 1 MAC isoflurane inhalation for 30 min before ischemia, followed by ischemia-reperfusion in group ISO-IR,and 1 MAC isoflurane inhalation for 30 min, followed by continuous perfusion in group ISO-C,and continuous perfusion without ischemia was given in group C. The changes of arterial blood gas analysis,lung wet-to-dry weight ratio （W/D）, malondialdehyde （MDA） and myeloperoxidase （MPO） of lung were studied at 45 min after pulmonary ischemia and at 30, 60, 120 min after reperfusion. The cell counts, percentage of polymorphonuclear neutrophil （PMN） and total protein （TP） content in left bronchoalveolar lavage fluid （BALF） were obtained at 120 min of reperfusion. Results During reperfusion, the lung W/D, MDA content and MPO activity in group IR and ISO-IR were increased progressively and significantly higher than those in group C and ISO-C （P〈0.05） ,but preadministration of isoflurane inhibited the increases in the lung W/D, MDA content and MPO activity after 60 min of reperfusion （P〈0.05）. The percentage of PMN in BALF of group IR was obviously increased compared with that of the other groups at 120 min of reperfusion （P〈0.05）. TP content in BALF significantly increased in group IR and ISO-IR more than that in group C, but the degree of increase in TP content of group ISO-IR was decreased markedly compared with that of group IR （P〈0.05）. Histological examination showed that the degree of injury in group ISO-IR was significantly ameliorated compared with that in group IR. Conclusion Inhalation of isoflurane before ischemia could protect the lung against ischemia-reperfusion injury in rats.