NF-κB、iNOS在大鼠实验性结肠炎肠组织的表达及意义

Expression and significance of NF-κB、iNOS in colon tissues of rats with TNBS-induced colitis

目的 观察大鼠实验性溃疡性结肠炎肠组织核因子 κB(NF κB)及iNOS、NO的表达 ,探讨NF κB在溃疡性结肠炎发病过程中的作用。方法 采用三硝基苯磺酸 (TNBS)制备大鼠溃疡性结肠炎模型 ,动物分为正常组、生理盐水组及轻、重模型组共 4组。采用免疫组织化学染色检测肠组织NF κB、iNOS表达 ,生化方法检测MPO、NO含量 ,并分析NF κB活性与肠道病理损伤指数、MPO、NO含量及iNOS表达的关系。结果 与正常组及生理盐水组相比 ,溃疡性结肠炎大鼠肠组织中NF κB活性 ,iNOS表达及NO含量、MPO活性显著增高 (P <0 .0 1) ,且在病情严重组增高尤为明显。NF κB表达水平与iNOS阳性细胞密度、NO含量、MPO活性及肠道病理损伤指数呈显著正相关关系 (P <0 .0 1)。结论 NF κB、iNOS可能参与了溃疡性结肠炎发生。

Objective To investigate the role and the expression of NF-κB and iNOS in the pathogenes is of TNBS-induced colitis in rats.MethodsSprague-Dawley rats w ere randomly d ivided into four groups:normal group,NS group ,model groupⅠ,model groupⅡ;Rat c olitis model was induced by 2,4,6-trinitrobenzene sulfonic acid(TNBS),The NF- κB 、iNOS protein expression in colon tissue were examined by immunohistochemis try.Biochemistry was used to detect the myeloperoxidase(MPO) activity and conten t of nitric oxide(NO) in the mucosa, Meanwhile, the macroscopical and histologic al changes of the colon were evaluated and the correlation between activity of NF-κB with each index was examined.Resultsthe activity of NF-κB and expressi on of iNOS,MPO activity and content of NO in rats of model group was higher than that of normal control( P <0.01),especially in model Ⅱ group the expression of NF-κB showed a strong corre lation with the positive expression of iNOS、MPO activity、the content of NO、ma croscopical and histological changes in TNBS-induced colitis, respectively.ConclusionNF-κB and iNOS may participate in the occurrance and d evelopment of TNBS-induced colitis.