Abstract:

Abstract:Objective  To observe the effect of salmeterol(SLM) on inflammatory factors in bronchial veolar lavage fluid(BALF) of rats with bronchial asthma,and to investigate the therapeutic mechanism of salmeterol on bronchial asthma.Methods  48 SD rats were divided into 4 groups randomly:blank control group,model group,SLM group and inderal +SLM group.BALF of rats in various groups was collected.Then the eosinophil(EOS) was counted under light microscope,the apoptotic index of EOS was detected by TUNEL,and the levels of interleukin-5(IL-5)　 and Eotaxin were detected by ELISA.The pathological changes of lung tissues were observed by HE staining.Results  The levels of EOS,Eotaxin and  IL-5 in BALF of rats in model group and inderal +SLM group were all higher than those in blank control group (P<0.01).The apoptotic indexes in model group and inderal +SLM group were lower than that in blank control group(P<0.01).The levels of EOS,Eotaxin and IL-5 in BALF of rats in SLM group were all lower than those in model group(P<0.01).The apoptotic index in SLM group was higher than that in model group  (P<0.01).Inflammation was significant in lung tissues in model group and inderal +SLM group.Inflammation was mild in lung tissues in  SLM group.Conclusion The therapeutic mechanism of SLM on bronchial asthma may be related to lowering the number of EOS by the way of adrenoceptor-β2 to depress Eotaxin and IL-5 in BALF of asthma rats.

Key words: salmeterol;bronchial asthma;eosinophil;Eotaxin;interleukin-5;apoptotic index;rats