肺表面活性物质对哮喘大鼠ET-1及ET-1 mRNA表达的影响

目的:观察吸入肺表面活性物质(PS)对哮喘大鼠模型哮喘发作、内皮素-1(ET-1)及支气管肺组织ET-1 mRNA表达的影响,探讨PS 防治哮喘的机制.方法:建立哮喘大鼠模型,氧气驱动雾化吸入PS,观察哮喘发作情况及肺组织病理变化;采用放射免疫法测定其血浆及支气管肺泡灌洗液(BALF)中ET-1含量 ,以分子原位杂交技术检测支气管肺组织内ET-1 mRNA的表达.结果:哮喘组血浆、BALF中ET-1含量及支气管肺组织ET-1 mRNA表达明显增加;治疗组哮喘发作及病理改变减轻,ET-1含量、支气管肺组织内ET-1 mRNA的表达较哮喘组明显减少.结论:ET-1在哮喘发病机制中可能发挥重要作用,外源性PS能减轻哮喘发作,可能与抑制ET-1 合成及释放有关.

Effect of pulmonary surfactant on expression of endothelin-1 and endothelin mRNA in rats with allergic asthma

Objective: To observe the effect of pulmonary surfactant (PS) on endothelin 1 (ET 1) in asthmatic rats and discuss the mechanism of the preventive and therapeutic effect of PS on asthma. Methods: The models of asthmatic rats were set up and treated with inhaled PS driven by oxygen before evoking them. The asthmatic condition and the pathological condition of their bronchopulmonary tissue were observed. The concentration of ET 1 in plasma and BALF was tested with radioimmunoassey and the distribution of ET 1 mRNA in lungs was shown with in situ hybridization technique. Results: In the asthmatic group, ET 1 of plasma and BALF and the distribution of ET 1 mRNA in lungs increased significantly than that in controls. PS alleviated asthmatic condition and pathological variation. Meanwhile, in the therapeutic group, ET 1 and ET 1 mRNA expression of their bronchopulmonary decreased signficantly than that in asthmatic rats. Conclusion: ET 1 may play an important role in the pathogenesis of asthma and exogenous PS may prevent or improve asthma through reducing the synthesis and release of ET 1.