中文摘要：

目的探讨在转化生长因子（TGF）β1致大鼠肾小管上皮细胞（NRK52E）发生上皮细胞向间质细胞转分化（EMT）过程中囊泡型H^＋-ATP酶（V—ATPase）B亚基的变化及其可能意义。方法NRK52E细胞无血清培养后予TGF—β1（10μg／L）刺激不同时间（0、6、12、24、48、72h），应用实时定量PCR、Western印迹、免疫荧光技术检测仅平滑肌肌动蛋白（α—SMA）、E钙黏素（E—cadherin）、V—ATPaseB亚基（B1、B2）mRNA、蛋白表达及分布的变化。结果TGF-β1刺激NRK52E细胞48h后Ⅱ-SMAmRNA及蛋白表达显著上调，E—cadherin mRNA及蛋白表达显著下调，同时V—ATPaseB2亚基mRNA及蛋白表达也显著增加（均P〈0．05）。但是β1亚基在细胞内表达很低，刺激后也未见显著变化。免疫荧光也显示V—ATPaseB2亚基在细胞内的分布明显增加并向胞膜聚集。结论在NRK52E内主要分布的是V—ATPaseB2亚基。TGF-β1刺激NRK52EEMT过程中V—ATPaseB2亚基表达显著增加，这提示B2亚基可能参与肾小管EMT过程。

英文摘要：

Objective To investigate the change of V-ATPase B subunits on epithelial to mesencflymal transition （EMT） in rat renal tubular epithelial cells （NRK52E） stimulated by transforming growth factor β1 （TGF-β1）. Methods NRK52E cells were stimulated by TGF-β1 （10 μg/L） for 0 h （control）, 12 h, 24 h, 48 11, 72 h after serum-free culture for 24 h. The mRNA and protein expression of E-cadherin, α-SMA, B2 and B1 subunits of V-ATPase were detected by real-time PCR, Western blotting and immunofluorescenee. Results After stimulated by TGF-β1 （10 μg/L） for 48 b, the expression of α-SMA was markedly increased （P〈0.05）, but the expression of E-cadherin was dramatically decreased （P〈0.05）. Meanwhile, the expressions of V-ATPase suhunit B2 was signifieantly increased （P〈0.05）. However, the B1 subunit distributed rarely in NRK 52E eells, and did not increase after TGF-β1 stimulation. Double-label irnmunofluoerscenee staining also showed that the V-ATPase B2 subunit was increased in the eytoso, tending to accumulate to the cell membrane after TGF-β1 stimulation. Conclusions The main isoform of V-ATPase distributed in NRK52E cells is B2 subunit. B2 subunit is increased alone with TGF-131-induced EMT. It may suggest that V-ATPase B2 subunit may play a potential role in TGF-β1- induced tubular EMT and renal fibrosis.