内毒素致急性肺损伤大鼠水通道蛋白1、5表达的影响

目的:观察细菌内毒素(LPS)致急性肺损伤(ALI)大鼠肺组织的变化,探讨大鼠急性肺损伤模型的复制.方法:SPF级雄性SD大鼠42只,随机分为ALI组和正常对照组(NS组),每组21只.ALI组子LPS(4 mg·kg-1,浓度4 mg·ml-1)舌下静脉注射；NS组予生理盐水0.2ml舌下静注,动态观察注射后2,6,12 h肺组织湿干质量(W/D)、肺组织病理学改变、支气管肺泡灌洗液(BALF)的细胞总数及中性粒细胞百分比、免疫组化与Western blot法肺组织AQP1蛋白表达的变化.结果:与NS组相比,ALI组大鼠W/D值、BALF细胞总数、中性粒细胞百分比、免疫组化与Western blot法肺组织AQP1、5蛋白表达的变化于LPS静脉注射后2h开始升高,第6 h达高峰.ALI组与NS组各时相点间的差异均具有统计学意义(P＜0.05).结论:静脉注射LPS可导致大鼠ALI,肺炎症损伤反应的高峰于LPS致伤后6～12h最为明显.

Expression of Aquaporin 1,5 in Rats with Endotoxin induced Acute Lung Injury

ObjectiVe： To study the change of aquaporin （AQP） 1,5 levels in the lung tissue of rats with bacterial endotoxin （LPS）-induced acute lung injury （ALI） in order to explore the pathogenesis of pulmonary edema. Method： Forty-two male SPF SD rats were randomly divided into two groups, namely the ALl group and normal control group （ NS group）. The ALI group was given LPS of 4 mg. ml- 1 with the dose of 4 mg·kg- 1 by sublingual intravenous injection, and the NS group was given saline0.2 mt at the same time. Observation was carried out at 2,6 and 12 h after the administration with the indices of lung tissue wet-dry weight （W/D） ,patho- logical changes of lung tissue, bronchoalveolar lavage fluid （BALF） total cells and percentage of neutrophils, AQP 1,5 protein expres- sion changes detected by immunohistochemical method and Western blotting. Result： Compared with the NS group, W/D values, BALF total cells and neutrophil percentage at 2 h after the intravenous injection of LPS in the ALl group began to increase and reached the peak at 6 h. Lung tissue AQP 1,5 protein expression at 2 h decreased with significant reduction at 6 h and 12 h. The differences be- tween the ALI group and the NS group at all time points were statistically significant （ P 〈 0.05 ）. Conclusion ： The intravenous injec- tion of LPS can lead to acute lung injury and the pneumonia disease damage is the most obvious at 6-12 h after the administration. The reduction of AQP 1,5 protein expressions in lung injury rats suggests that AQP 1,5 may be involved in the occurrence of lung injury.