目的 探讨乌司他丁保护脂多糖诱导急性肺损伤的作用机制.方法 30只wistar大鼠随机均分成3组,A组:正常对照组;B组:注射脂多糖诱导急性肺损伤模型;C组:模型建立30分钟后静脉注射乌司他丁.6h后处死大鼠取其肺组织,行肺组织病理检测,测量湿干比,酶联免疫吸附测定法检测各组肺泡灌洗液中炎性因子IL-6和TNF-α的水平,Western-blotting检测肺组织ICAM-1和GAPDH蛋白含量.结果 B组湿干比显著高于A组(P＜0.01),C组湿干比显著低于B组(P＜0.05);B组肺泡灌洗液IL-6和TNF-α水平均显著高于A组(P＜0.01),而C组均显著低于B组(P＜0.01);B组肺组织ICAM-1蛋白表达水平显著高于其他两组(均P＜0.01),C组ICAM-1水平显著低于B组(P＜0.01),但高于A组(P＜0.05),GAPDH在三组中的表达量无显著差异.结论 乌司他丁通过减轻肺组织炎性反应,降低ICAM-1在肺组织中的表达水平来发挥其保护作用.“,”Objective To investigate the mechanism of ulinastain in protecting the lung against acute lung injury (ALI) induced by lipopolysacharide (LPS).Methods Thirty Wistar rats were randomly divided into 3 equal groups:Group A,normal control group,Group B,undergoing LPS injection to cause ALI,and Group C undergoing intravenous injection of ulinastatin 30 min after the model establishment.The rats were killed 6 hours later with their lungs taken out.Pathological examination was conducted.Wet to dry weight ratio was messured.Enzyme linked immunosorbent assay was used to test the levels of Inflammatory factors interleukin (IL)-6 and tumor necrosis factor-cα (TNF-α) in the bronchoalveolar lavage fluid (BALF),Western-blotting was used to detect the protein expression level of intercellular cell adhesion molecule-1 (ICAM-1) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH).Results The wet to dry weight ratio of Group B was significantly higher than that of Group A (P ＜0.01),and the wet to dry weight ratio of Group C was significantly lower than that of Group B (P ＜0.05).The histologicaal ferature of the lung tissue of Group A was normal,significant iInflammation phenomena were seen in the lung tissue of Group B,and the pathological changes were obviously milder in Group C in commparison with Group B.The BALF levels of IL-6 and TNF-cα of Group B were both significantly higher than those of Group A (both P ＜ 0.01),and the BALF levels of Il-6 anf TNF-α of Group C were both significantly lower than those of Group B (both P ＜ 0.01).The ICAM-1 protein expression level in lung tissue of Group B was significantly higher than those of the other 2 groups (both P ＜ 0.01),and the ICAM-1 protein expression level in lung tissue of Group C was significantly lower than that of Group B (P ＜ 0.01),however,still significantly higher than that of Group A (P ＜0.05).There was no significant differences in the protein expression level of GAPDH among these 3 groups.Conclusion Ulinastatin lessens inflammatory reaction of lung tissue and decreases the expression of ICAM-1 in lung tissues,thus exerting its protective effects.