Objective:To investigate whether transplantation of mesenchymal stem cells(MSCs) through renal arteries can protect kidney from acute tubular necrosis(ATN),so as to lay a foundation for MSC transplantation in treatment of ATN.Methods: Five-week-old nude mice were randomly divided into three groups:normal control group(n=10),acute tubular necrosis(ATN) model group without(n=10) and with MSCs treatment group(n=11).ATN nude mice were induced with 50% glycerin.MSCs labeled with enhanced green fluorescent proteins(EGFP) were injected into kidney through renal arteries.Serum creatinine was determined in all groups and pathological changes of renal tissues were detected using H-E staining.The amount and distribution of the EGFP-marked MSCs in renal tissues were determined with fluorescence microscope.Results: Degeneration and exfoliation of renal tubular epithelial cells,and even renal tubular tamponade with cast-off cells were observed in the ATN group; these pathological changes were mainly located at renal cortex and juncture of renal cortex and medulla.The damages were greatly alleviated in the ATN+MSCs transplantation group,with no swelling of epithelial cells,nuclear condensation or edema.Fourteen days after MSCs transplantation,EGFP positive cells were increased in renal tubules of recipient mice.Conclusion: The MSCs transplantation via renal artery can locate in renal tubular epithelium,and promote the repair of injured renal tubular epithelial cells.