Expression Of Aquaporin 5 And Changes Of Tumor Necrosis Factor α, Interleukin 13, Leukotriene B₄ In Lipopolysaccharide-Cigarette Smoking Inducible Chronic Bronchitis Rat Model

Objective To investigate the correlation between the inflammatory mediators tumor necrosis factorα(TNF-α), interleukin 13(IL-13),leukotriene B 4 (LTB4) and the expression of aquaporin 5, and the influence of the former from ambroxol chloride.Methods 21 Sprague-Dawley (SD) rats were randomly divided into three groups : ambroxol chloride treatment group ( group A) with intraperitoneal injection of ambroxol chloride basing on chronic bronchitis model, chronic bronchitis model group( group B) induced by lipopolysaccharide instilling into the tracheas of experimental rats combining cigarette smoking, control group(group C). TNF-α, IL-13 and LTB4 were determined from lung homogenate supernatant, bronchial alveolar lavage fluid (BALF) and serum by enzyme-linked immunosorbent assay (ELISA). Semiquantitative in-situ-hybridization and immunohisto- chemistry was used to measure the expression of aquaporin 5 in bronchial epithelia and alveoli. All statistical calculations, including analysis of variance, q test and Pearson's correlation analysis were performed using the statistical package SPSS version 11.0.Results (1) Pathology:The typical pathologic manifestations of chronic bronchitis were observed in the SD rats of group A and group B. (2) TNF-α, IL-13, LTB4 ELISA:TNF-αof group B from lung homogenate supernatant and BALF was more than those of group A and C (both P <0.01), but TNF-αin serum wasn't different among three groups. Only IL- 13 of group A from lung homogenate supernatant was less than that of group C(P <0.05),but others weren't different. LTB4 of group B from BALF was more than those of group A and C (P <0.01 and P <0.05 respectively), but others weren't different. (3) Expression of AQP5:The positive expression ratio and the relative expression magnitude of aquaporin 5 in bronchial columnar epithelia of group B were less than those of group A and C (all P <0.01), but those weren't different between group A and group C. The expression of AQP5 wasn't different among three groups in alveoli except for the positive expression ratio of AQP5 being different...