脓毒症性ARDS大鼠肺泡表面活性物质结合蛋白的变化及乌司他丁的干预效果

Changes of pulmonary surfactant protein and protective effects of ulinastatin on septic ARDS in rats

目的:观察乌司他丁注射液干预前后盲肠结扎穿孔法(CLP)致脓毒症性急性呼吸窘迫综合征(ARDS)大鼠肺泡表面活性物质的改变,探讨表面活性物质在CLP致ARDS发生中的作用以及乌司他丁对其影响。方法:健康成年SD大鼠90只,体质量200~240 g,随机分为3组:假手术对照组(Sham组,n=30)、脓毒症组(CLP组,n=30)和乌司他丁组(UST组,n=30)。利用CLP法建立大鼠脓毒症模型。测定各组大鼠造模后6、12、24、48 h四个时间点肺湿/干质量比(肺水肿指数);使用苏木精-伊红(HE)染色方法和透射电镜对肺组织进行病理观察及急性肺损伤病理评分;通过实时荧光定量核酸扩增技术(RT-PCR)和免疫印迹试验(WB)分别检测肺泡表面活性物质结合蛋白B(SP-B)和肺泡表面活性物质结合蛋白C(SP-C)在mRNA水平和蛋白质水平的表达情况。结果:与对照组相比,肺水肿指数和肺损伤病理评分显示乌司他丁组大鼠肺损伤明显减轻(P<0.05);乌司他丁组大鼠肺组织中SP-B和SP-C在mRNA水平和蛋白质水平的表达都较CLP组明显升高(P<0.01)。结论:乌司他丁可以提高脓毒症性ARDS大鼠肺泡表面活性物质结合蛋白含量,有效减轻肺损伤。

Objective： To investigate the changes of pulmonary surfactant protein as well as protective effects and mechanisms of ulinastatin in rats with septic acute respiratory distress syndrome（ ARDS） induced by cecum ligation and puncture（ CLP）.Methods： Ninety healthy adult SD rats（ weighing 200-240 g） were randomized into sham operation group（ Sham group,n = 30）,sepsis group（ CLP group,n = 30） and ulinastatin treatment group（ UTI group,n = 30）. Septic rat models were prepared by conventional CLP technique. Rats in each group were sacrificed at 6,12,24 and 48 h after successful model development,and lung tissues were taken and weighed to calculate the wet / dry（ W / D） index. Hematoxylin eosin（ HE） staining was performed and transmission electron microscope was used to observe the pathological changes of the lung and rate the degree of acute injury. The RT-PCR and Western blot were performed to respectively quantify the surfactant protein B（ SP-B） and surfactant protein C（ SP-C） mRNA expression and protein level.Results： As compared with CLP group,the survival rate of rats in UTI group was significantly increased（ P〈0.01）,with lower pulmonary edema index and pathological scores representing lung injury（ P〈0.05）. The mRNA and protein levels of SP-B and SP-C were dramatically increased in rats in the UTI group.Conclusion： Ulinastatin injection may efficiently reduce lung injury as well as improve the survival rate of rats with septic ARDS and up-regulate the SP-B and SP-C expression.