Objective:To investigate the expression of peroxisome proliferator-activate receptor γ(PPARγ) in the kidneys of rats at different ages,so as to study the possible association of PPARγ expression with oxidative stress in the aging process.Methods: Rat aging model was established using 3-,12-,and 24-month old rats.Western blotting was used to determining the protein expression of PPARγ.The changes anti-oxidative ability of renal tissue were studied by determining the activities of superoxidedismutase(SOD)and glutatio-neperoxidase(GSH-PX).Results: Western blotting assay showed that the renal expression of PPARγ protein decreased with the aging of rats,with that of 3-month group significantly higher than that of the 24-month group(P<0.01).The activities of SOD and GSH-PX deceased with the aging of rats(P<0.01).Both the SOD activities were positively correlated with the expression of PPARγ protein(r=0.90,r=0.89,P<0.01) Conclusion: Renal PPARγ has a decreasing tendency during the aging process of rats,which is correlated with the down-regulation of anti-oxidative ability of renal tissue.