Effect of ambroxol on the bronchil mucosa ultrastructure and IL-8 TNF-α in BALF in smoking rats

Objective:To observe the effect of ambroxol on chronic bronchitis in smoking model of rat.The changes of ultrastructures of bronchus,cell count and the level of interleukin-8(IL-8)and tumor necrosis factor-a(TNF-α)in the bronchoalveolar lavage fluid(BALF)in animal were observed.Method:Rats were randomly divided into three groups:1.control group(n=10);2.smoking group(n=10);3.Ambroxol intervention group(n=10).Chronic bronchitis in group ② and ③ established by passive cigarette smoking.In group ③,ambroxol was administrated 40 mg/kg daily for 2 months before the rats were dead.The ultrastructures of bronchial mucosa were observed by scanning electron microscope.The levels of IL-8 and TNF-α and cell count in BALF was detected by ELISA and Wright's staining separately.Result:Smoking group manifested epithelial cell cilia of bronchial mucosa lossing、lodging and twisting,microvilli of chalice cell decreasing,inflammatory cell infiltrating,epithelial cell atrophing,chalice cell in region increasing,microvillus decresing.The surface of ciliated cell is thin and flat.These feature correspond with the of human chronic bronchitis.Compared with the control group,the ambroxol intervention group appeared pathological changes of tracheal and bronchial epithelium cell.The numbers of total cells and neutrophil in BALF of the smoking group and the ambroxol group were significantly increased compared to the control group(P0.01).The numbers of total cells and neutrophil in BALF of the ambroxol group were significantly decreased compared to the smoking group(P0.05).The level of IL-8 and TNF-α in BALF of the smoking group was significantly increased compared to the control group(P0.01).whereas the ambroxol group was significantly decreased compared to the smoking group(P0.01).Conclusion:Smoking could cause obviously bronchial mucosa to loss epithelial cell cilia,decrease microvilli chalice cell,increase of IL-8、TNF-α、cell counting in BALF.Inflammation of airway could be alleviated by using ambroxol.