Abstract: Objective To explore the expression of snail1 in renal tissues of diabetic rats ,and to investigate its contribution to the progression of diabetic nephropathy.Methods Rats were randomly divided into control groups,DM and insulin-treated groups . The protein and(or) mRNA expression of Snail1，E-cadherin, α-SMA and FN in renal tissue were detected. Results The Snail1 protein strongly positive stainings were observed in renal tubules of DM rats. In DM rats α-SMA tubules staining were seen from 16th week. The proteins and mRNA of Snail1 and FN were significantly up-regulated in renal cortex of diabetic rats（P＜0.05）, while down-regulated in the insulin-treated diabetic rats （P＜0.05）. The expression of E-cadherin protein and mRNA were contrary to the snail1.Conclusion These findings suggest that snail1 expression is up-regulated in the renal tubules of rats with DM , which may involve in the pathogenesis of diabetic nephropathy by inducing FN and tubular epithelial-mesenchymal transition.

Key words: Snail1, E-cadherin, α-SMA, Diabetic nephropathy, rat