吸入一氧化氮对内毒素性急性肺损伤大鼠的作用

Effects of NO Inhalation on Endotoxin-induced Acute Lung Injury

目的观察并评估吸入一氧化氮(iNO)对内毒素性急性肺损伤大鼠肺部炎症和损伤程度的影响。方法 80只雄性清洁级SD大鼠随机分成4组:空白对照吸入空气(C+RA)组、空白对照吸入一氧化氮(C+iNO)组、脂多糖给药后吸入空气(L+RA)组和脂多糖给药后吸入一氧化氮(L+iNO)组。腹腔注射20%乌拉坦麻醉后建立静脉通路。L+RA组和L+iNO组股静脉输注脂多糖2mL(6mg/kg溶于2mL生理盐水);C+RA组及C+iNO组股静脉输注生理盐水2mL(脂多糖溶剂对照);静脉输注完成后马上将C+iNO组和L+iNO组大鼠放入特制的密封盒内[NO终浓度稳定在(40±2)ppm];C+RA组和L+RA组则放置于实验室吸入空气。观测各组肺组织病理改变;测定支气管肺泡灌洗液(BALF)中总蛋白浓度;同时检测肺组织髓过氧化物酶(MPO)活性和丙二醛(MDA)浓度。结果与C+RA组及C+iNO组相比,L+RA组大鼠的肺组织炎症损伤程度、BALF中总蛋白浓度、MPO活性、MDA浓度均显著增高(P<0.05或0.01);而与L+RA组比较,L+iNO组大鼠肺组织的炎症损伤程度、BALF中总蛋白浓度、MPO活性、MDA浓度均显著减轻或下降(均P<0.05)。结论吸入一氧化氮可改善内毒素导致的急性肺损伤,其可能的机制在于一氧化氮能抑制脂质过氧化反应,减少自由基的产生。

Objective To investigate the therapeutic effects of NO inhalation on endotoxin-induced acute lung injury（ALI）.Methods Eighty SD rats were randomly assigned to the C＋RA group,C＋iNO group,L＋RA group,and L＋iNO group.The lung was removed for pathohistological changes and total protein levels in bronchoalveolar lavage fluid（BALF）.The levels of MPO and MDA were measured.Results Endotoxin administration resulted in pulmonary edema and increased protein levels in BALF.There were increased MPO and MDA levels in the lung tissue.NO inhalation attenuated the pulmonary edema and decreased the protein levels in BALF.Furthermore,NO inhalation decreased the protein levels in BALF and the levels of MPO and MDA.Conclusion NO inhalation attenuated the lung injury in endotoxin-induced ALI model by inhibiting the lipid peroxidation reaction and decreasing free radicals.