乌司他丁对爆炸致家兔急性肺损伤的治疗效果及初步机制研究

Efficacy and mechanism of ulinastatin on acute lung injury induced by blast in rabbits

目的:探讨不同剂量乌司他丁(UTI)对爆炸致急性肺损伤(ALI)的治疗效果,并探讨其作用机制。方法:制作爆炸致家兔急性肺损伤模型,选择家兔40只,随机分为5组,每组8只:空白对照组(N组)、模型组(ALI组)和低、中、高剂量UTI干预组(L/M/H组)。造模完成后,L/M/H组分别注射(2.5,5,10×104U·kg-1)UTI溶液,N组与ALI组静脉注射等量0.9%Na Cl溶液。24 h后取支气管肺泡灌洗液(BALF)、血液及肺组织,用ELISA方法检定BALF及血清中TNF-α,IL-6的含量,蛋白印迹法和RT-PCR方法测定肺组织MMP-9蛋白和mRNA的表达水平,测定肺湿干重比,光镜下观察肺组织病理学变化。结果:ALI组湿干重比(W/D),TNF-α,IL-6以及基质金属蛋白酶-9(MMP-9)表达量均较N组升高(P<0.05),L/M/H组的W/D,TNF-α,IL-6表达量均较ALI组降低(P<0.05),以H组最为显著(P<0.05);肺病理检查显示M和H组肺组织肺水肿、炎症反应等较ALI组明显减轻。结论:乌司他丁可通过降低MMP-9的表达,抑制TNF-α,IL-6细胞因子的产生、释放,减轻爆炸致急性肺损伤的肺部损伤,高剂量干预效果更显著,UTI可能成为临床救治急性肺损伤的潜在用药之一。

Objective： To study the effect and mechanism of different doses of ulinastatin（ UTI） on acute lung injury（ ALI） induced by blast in rabbits. Methods： The models of acute lung injury induced by blast were made in rabbits. All the rabbits were randomly divided into 5 groups： normal group（ N group）,model group（ ALI group）,and UTI groups of different doses（ L / M / H group）,with 8 rabbits in each group. When the model was established,the rabbits in groups L / M / H were intravenously injected with different doses of UTI（ 2. 5,5,10 × 104U·kg^-1）,and the rabbits in group N and group ALI were injected with normal saline of the same volume. Bronchial alveolar lavage fluid（ BALF）,blood,and some lung tissue samples were taken at 24 h. TNF-α and IL-6 were determined by ELISA method. MMP-9 was evaluated by Western blotting and reverse transcription polymerase chain reaction. The wet to dry weight ratios were determined. The pathological changes of lung were observed under microscope. Results： The wet to dry lung weight ratios and the levels of TNF-α,IL-6,MMP-9 in group ALI weresignificantly higher than those in group N（ P〈0. 05）. The wet to dry weight ratios and the levels of TNF-α and IL-6 in groups L / M / H were lower than those in group ALI,and group H had the most significant difference（ P〈0. 05）. Histopathology examination of lung tissue showed that pulmonary edema and inflammatory in groups M / H were significantly relieved than those in group ALI. Conclusion： UTI could relive inflammation in the lungs of rabbits caused by ALI induced by blast through reducing excessive release of MMP-9 and inflammatory mediators.UTI can be a potential drug for treatment of ALI.