Objective To observe the phenotypic transformation of bone marrow mesenchymal stem cells(MSC) transfected with hepatocyte growth factor(HGF) after their transplantation in the rat's kidney with partial unilateral ureteral obstruction(PUUO).Methods We isolated,cultured bone MSCs of the male rats,and transfected them with Ad-HGF in vitro.Thirty-six female rats with PUUO were randomly divided into control group(A) and the experimental groups(B,C).Saline,Ad-GFP transfected MSCs or Ad-HGF transfected MSCs were respectively injected into the parenchyma of kidney on the 7th day with PUUO.We released the ureteral obstruction of rats after transplantation.Kidney tissue of the rats were collected on the 7th day after transplantation.The distribution and phenotypic transformation of MSCs in the kidney were determined by immunofluorescence method.Results The green fluorescent-labeled MSCs mainly distributed in the tubular cells,and a part of bone MSCs underwent phenotypic transformation after transplantation.Compared with group B,the number of bone MSCs with phenotypic transformation significantly increased in group C.Conclusion After transplantation,MSCs can survive and differentiate into renal tubular epithelial cells,and HGF may promote survival and differentiation of MSCs.