实验性肺纤维化大鼠组织整合素α5β1和转化生长因子—β的表达

目的 研究纤维连接蛋白受体整合蛋白受体整合素α５β１在大鼠肺纤维化中的作用。方法 用免疫组化方法观察实验性大鼠肺纤维化纤维连接蛋白及其受体整合素α５β１和转化生长因子－β表达的动态变化：用Ｎｏｒｔｈｅｍ印迹杂交和免疫细胞化学方法观察ＴＧＦ－β对体外培养的大鼠肺成纤维细胞整合素α５β１ ｍＲＮＡ和 白表达的影响。结果 （１）实验组１￣３天,病灶内上皮细胞和骨皮细胞整合素α５β１表达明显增强,炎细胞及

The expression of integrin alpha5beta1 and transforming growth factor-beta in pulmonary fibrosis of rat

OBJECTIVE: To study the roles of integrin alpha(5)beta(1) played in rat pulmonary fibrosis. METHODS: The dynamic changes of fibronectin (FN), FN receptor alpha(5)beta(1), and TGF-beta were analysed in bleomycin-induced rat pulmonary fibrosis by using immunohistochemical technique. Northern blot analysis and immunocytochemistry techniques were performed in order to detect the expression of alpha(5)beta(1), FN mRNA and their relevant proteins in cultured rat pulmonary fibroblasts (PFbs) after administration of TGF-beta1. RESULTS: (1) A strong positive reaction with anti-integrin alpha(5)beta(1) was seen in the pneumocytes, endothelial cells and proliferated mesenchymal cells on the 1st to 3rd day after bleomycin. The positive signals for integrin alpha(5)beta(1) were apparent mainly in those proliferated interstitial cells with fibroblast and myofibroblast differentiation 7 days after bleomycin treatment. Changes in FN were similar to that of the integrin alpha(5)beta(1). (2) Expression of alpha(5)beta(1), FN mRNAs and their relevant proteins was increased in rat PFbs after TGF-beta1 administration. CONCLUSIONS: Integrin alpha(5)beta(1) played a key role in inducing the activation, proliferation and differentiation of PFbs, causing an increase of extra-cellular matrix synthesis during pulmonary fibrogenesis.