转化生长因子β1及其信号蛋白在大鼠急性腹膜炎模型腹膜组织中的表达及作用  

Expression of TGF-bbbbbbb1/Smads in rat inflamed peritoneum

作　　者：王欣[1] 余学清[1] 贾占军[1] 郑智华[1] 陈文芳[1] 李晓艳[1] 彭文兴[1] 窦献蕊[1] 孙辽[1] 

机构地区：[1]中山大学附属第一医院肾内科,广州510080

出　　处：《中华肾脏病杂志》2004年第6期391-395,共5页Chinese Journal of Nephrology

基　　金：广州市科学委员会重点项目(2004Z2-E0041)教育部国际合作项目(教外司留[2001]498号)

摘　　要：目的 通过观察转化生长因子β1(TGF-β1)及其信号蛋白Smads的表达水平和活性状况,探讨其在细菌性腹膜炎介导腹膜纤维化过程中的可能作用。方法 通过腹腔注射E.coli ATCC25922造成大鼠急性细菌性腹膜炎的动物模型。应用激光共聚焦显微镜检测TGF-β1、p-Smad2／3和Smad7在大鼠腹膜组织的表达和活化,以单位面积的平均荧光强度半定量地分析其蛋白水平的表达及动态变化。应用RT-PCR的方法分析TGF-β1、Smad3和Smad7在基因水平的表达。结果 E.coli腹腔注射后大鼠血白细胞显著降低而腹水白细胞显著升高。组织学显示间皮下层水肿样增厚,脏层和壁层腹膜大量炎症细胞灶性浸润。免疫荧光结果显示TGF-β1和p-Smad2／3广泛表达于炎症细胞、间皮细胞和血管内皮细胞。半定量的免疫荧光结果显示TGF-β1、p-Smad2／3和Smad7的表达都呈双峰样上调,但Smad7的整体表达水平一直很低。TGF-β1、Smad3和Smad7 mRNA的表达水平与其蛋白表达水平基本一致。结论炎症状态下腹膜组织TGF-β1／Smad信号通路显著上调和激活。腹膜间皮细胞的活化以及其TGF-β1和p-Smad2／3的高表达,抑制性信号蛋白Smad7的低表达,可能参与了腹膜炎介导腹膜纤维化的过程。Objective To investigate the expression and activation of TGF-β1/Smads in inflamed peritoneum and to explore the potential role of TGF-β1/Smads in the progress of peritonitis associated fibrosis. Methods To induce the acute peritonitis the rats were given intraperitoneal injection with E. coli ATCC 25922 107 CFU in 10ml phosphate-buffered saline (PBS) per rat. The expression and activation of TGF-β1/Smads were measured by confoeal microscope. The expression of TGF-β1, p-Smad2/3 and Smad7 in protein level was measured by the mean fluorescence intensity. The mRNA expression of TGF-β1, Smad3 and Smad7 was measured by RT-PCR. Results The rats got a significant decrease of WBC in blood and substantial increase of the WBC in peritoneal fluid after the E. coli challenge. Histology showed that the submesothelial zone became thickened with the edematous changes and obvious WBC infiltration in both parietal and visceral peritoneum. The result of immunofluorescence(IF) showed that the expression of TGF-β1, p-Smad2/3 and Smad7 was found not only in the inflammatory cells but also in the mesothelial cells and endothelial cells. Semi-quantitative IF showed the expression of TGF-β1, p-Smad2/3 and Smad7 up-regulated, but the whole level of Smad7 was pretty low. The same trends as their protein were found in the mRNA expression of TGF-β1, Smad3 and Smad7. Conclusion The expression of TGF-β1/Smads increases in rat peritoneum after the E. coli challenge. The activation of mesothelial cells and the high expression of TGF-β1 and p-Smad2/3 accompanied with the low expression of Smad7 might contribute to the peritonitis associated fibrosis.

关 键 词：TGF-Β1 SMAD7 表达水平 SMAD2 腹膜组织 信号蛋白 大鼠 RNA 高表达 信号通路 

分 类 号：R572.2[医药卫生—消化系统]