Effects of Losartan on Renal Tubular Epithelial Cells Transdifferentiation in Streptozotocin-induced Diabetic Rats

Objective To observe the renal tubular epithelial cells transdifferentiation and the effects of Losartan on streptozotocin-induced diabetic rats,explore the renal protective mechanisms of ARB in DN.Methods Fifty Wistar rats were randomly divided into three groups:(1) Normal control group without streptozotocin-induced diabetes and without therapy(n=10);(2)diabetes without therapy group(n=20),(3)diabetes therapy group with Losartan 20 mg/Kg ·d~(-1)(n=20);Rat models of diabetic mellitus were established by intraperitoneal injection of 60 mg/kg streptozotocin.At sixteen weeks after therapy with Lorsartan,The alpha smooth muscle actin(α-SMA),vimentin and transforming growth factor-β1(TGF-β1)in renal tubular epithelial cells were detected by immunohistochemistry of SP method.Results The positive areas of α-SMA,vimentin and TGF-β1 in renal tubular epithelial cells of diabetic group were 0.3690±0.0587,0.1546±0.0141 and 0.3716±0.0657 respectively,showed stronger passivity in comparison with Lorsartan therapy group(P0.01).Conclusion Losartan can down-regulate expression of α-SMA,vimentin and TGF-β1 in diabetic renal tubular epithelial cells,restrain the process of epithelial myfibroblast transdifferentiation in diabetic rats.