Effect Of Pulmonary Surfactant On Endothelin-1,Atrial Natriuretic Peptide And Intercellular Adhesion Molecule-1 In Asthma

[Background] Asthma is a chronic pulmonary inflammatory disease, which involves a series of inflammatory cells and mediators in the airway. There exists marked dysfunction of pulmonary surfactant (PS) when asthma attacked. Previous studies indicated that exogenous PS could alleviate asthmatic attack. It is trusted that endothelin-1 (ET-1), atrial natriuretic polypeptide (ANP) and intercellular adhesion molecule-1(ICAM-1) is involved in the development of asthma. [Objective] To observe the effect of PS on ET-1, ANP, and ICAM-1 in animal asthma and discuss the mechanism of the prophylactic PS on asthma. [Method] We duplicated the models of allergic asthma, treated them with inhaling PS driven by oxygen before evoking them. We studied the pathology in the bronchopulmonary tissue. The concentration of ET-1 and ANP in plasma and bronchoalveolar lavage fluid (BALF) was tested with radioimmunoassey. The distribution of ET-1mRNA and ICAM-1 in lungs was shown with in situ hybridization and immunohistochemistry technique. [Results] 1. There were marked smooth muscle spasm, thickness of the wall, inflammatory cell infiltration and amount of exudate in the airway lumen in asthma group. The inflammatory exudation disappeared and smooth muscle spasm was alleviated in PS group. 2. In the asthmatic group, ET-1 of both plasma and BALF increased significantly than that in controls(p<0. 01). ET--l returned to the 1eve1 of the contro1s in PS group. 3. 1nthe asthmatic group, ANP of both p1asma and BALF increased significant1ythan those in contro1s. ANP of p1asma in PS group returned the 1eve1of the contro1s, but remained a high 1eve1 in BALF. 4. In the asthmaticgroup, the distribution of ET--1mRNA and 1CAM--l in airways increased'significant1y than that in contro1s. The ET--1mRNA and 1CAM1 expressionin their airways decreased significant1y in PS group.[Conc1usion] The resu1ts showed that exogenous PS cou1d re1ieve spasmof bronchio1e smooth musc1e and a11eviate the inf1anunatory process ofairway. PS may prevent or a11eviate asthma through regu1ating thesynthesis and express of ET--l, ANP and .ICAM--l.