胰岛素对脂多糖诱导的急性肺损伤大鼠肺水肿液清除的影响

Effects of insulin on alveolar fluid clearance in lipopolysaccaride-induced acute lung injury rats

目的探讨胰岛素对脂多糖(LPS)诱导的急性肺损伤(ALI)大鼠肺水肿液清除的影响。方法SD大鼠36只随机分为对照组、模型组和治疗组。模型组和治疗组给予LPS 5 mg·kg-1建立ALI模型,建模后1 h治疗组微量泵泵入含0.1 U.kg-1胰岛素的生理盐水1 mL·kg-1,对照组和模型组泵入生理盐水1 mL·kg-1,均作用8 h。观察3组肺组织病理形态学,测量肺湿干重比及肺泡液体清除率(AFC),免疫组织化学及Western blot测定肺泡上皮钠通道(ENaC)表达情况。结果治疗组大鼠血糖水平与模型组比较无显著差异(P>0.05)。与对照组比较,模型组大鼠动脉血氧分压下降,肺湿干比重增加,AFC下降,α-、β-和γ-ENaC表达下降,差异均有显著意义(P<0.05)。经胰岛素治疗后,治疗组大鼠动脉血氧分压与模型组比较升高,肺湿干重比显著下降,AFC增加,α-、β-和γ-ENaC表达增加,均有显著差异(P<0.05)。结论胰岛素能促进ALI大鼠肺泡水肿液体的清除,从而减轻肺水肿,其机制可能是通过上调α-、β-和γ-ENaC的表达实现的。

AIM To investigate the effects of insulin on alveolar fluid clearance （AFC） in lipopoly- sacccharide （LPS） -induced acute lung injury （ALI） rats. METHODS Thirty-six Sprague-Dawley rats were randomly divided into three groups, with 12 rats in each group. The rats in the model group and treatment group were received LPS at a dose of 5 mg-kg-1 to establish ALI model. One hour later, insulin was administrated at a dose of 0.1 U ,kg-1 .h-1 by micro- osmotic pump in the treatment group for 8 hours. Normal saline was administrated at a dose of 1 mL.kg-1 by micro-osmotic pump in the normal group and control group for 8 hours. The pathological changes in lung, lung wet/dry weight ratio and AFC were observed. The expressions of alveolar