Effects of tiotropium bromide on pulmonary surfactant protein D in serum and lung tissue of chronic obstructive pulmonary disease rats

Abstract

Objeetive To investigate the new mechanism of tiotropium bromide in the treatment of chronic obstructive pulmonary disease(COPD)by studying its effect on pulmonary surfactant protein D(SP-D) in serum and lung tissue of COPD rats.Methods We established the rat COPD models by passive smoking as well as intratracheal instillation of Lipopolysaccharide respectively. Thirty male SD rats were randomly divicied into the control group,the COPD group and the tiotropium bromide treatment group (n=10).The pathologic change of the lung tissue and airway were observed by HE staining.The level of SPD in serum was measured by enzyme-linked immunosorbent assay.The level of SP-D in lung tissue was detected by western-blot and immunohistochemistry.Results HE staining proved that the rat COPD models were successfully established.The COPD group appears obvious emphysema,while the treatment group appears mild emphysema.The expression of SP-D in serum and lung tissue of the COPD group were obviously stronger than that in the control group(P<0.01).The level of SPD in serum and lung tissue of the treatment group was between the control group's and the COPD group's.Conclusions Tiotropium bromide could reduce the level of SP-D in serum and lung tissue of COPD rat.These effects may be exerted through alleviating airway inflammation and the degree of emphysema. Key words: Chronic obstructive pulmonary disease; Tiotropium bromide; Pulmonary surfactant protein D