单次及多次应用肺表面活性物质对COPD鼠肺的保护作用比较

目的观察单次及多次应用外源性肺表面活性物质（PS）对实验性慢性阻塞性肺病（COPD）大鼠肺的保护作用比较。方法设立正常大鼠组和3个实验组：对照组（不用药）；PS一次干预组（PS1组，气道内注入PS1次，100mg／kg），PS多次干预组（PS3组，气道内注入PS3次，100mg／kg）。60d后测定动脉血气，光镜和透射电镜观察肺组织病理学改变；免疫组化法检测肺组织表面活性物质相关蛋白A（SP—A）的阳性表达。结果吸烟60d及气道内注入脂多糖2次，大鼠有明显的慢性支气管炎及肺气肿的变化，应用PS治疗1次，肺组织病变出现轻度改善，应用3次后肺组织损伤程度明显减轻，PaO2升高，PaCO2降低，SP—A表达增加。结论PS干预可减轻吸烟及LPS对肺组织的破坏，改善PaO2，抑制气道炎症，保护肺泡Ⅱ型上皮细胞和SP-A表达，从而可有效减轻COPD的肺部病变，且多次用药效果好。

Effects of Exogenous Pulmonary Surfactant on Experimental Chronic Obstructive Pulmonary Diseases in Rats

Objective To investigate the effects of pulmonary surfactant on experimental chronic obstructive pulmonary diseases in rats. Methods Sixty Wistar rats were randomly divided into 4 groups as followed ： normal group, control group, and treatment group （ PSI, PS3 ）. The last three groups received smoke inhalations daily for 60 days and received intratraeheal instillations of lipopolysaccharide twice, two of which received exogenous pulmonary surfactant treatment（ PS1 one time, PS3 three times, 100mg/Kg BW ）. Blood gas analysis,light microscopy and electromicroscopy observations were performed in each group. Pulmonary mean linear intercept （ MLI） , mean alveolar numbers （ MAN ） , and pulmonary alveolar area （PAA） were measured by image analysis. The expression of surfactant protein A （SP-A） were observed by immunohistochemistry. Results Smoking for 60 days and instillations of lipopolysaccharide twice resulted in chronic bronchitis and emphysema. MLI and PAA increased and MAN decreased in the three experimental groups compared with in the normal group. PaO2 decreased and PaCO2 increased in the three experimental groups compared with in the normal group. The expression of SP-A in the three experimental groups were decreased compared with in the normal group. Administration of exogenous pulmonary surfactant resulted in statistically significant inhibition of pulmonary injury,especially for 3 times. Conclusion Exogenous pulmonary surfactant for several times have a protective effect on COPD model of rats by alleviating airway inflammatory reaction, decreasing the destruction of alveolar.