Objective:To investigate the role of oxidative stress in aldosterone(ALDO)-induced mesangial cell(MC) proliferation,and to detect the inhibitory effect of peroxisome proliferator-activated receptor--酌(PPAR-酌) agonist on ALDO-induced MC proliferation. Methods:Mouse primary mesangial cells were treated with ALDO(100 nmol/L) in the presence or absence of N-acytosistin(NAC,10 -滋mol/L)or Rosiglitazone(1.0,2.3,5.0,10.0 -滋mol/L). MC proliferation was measured by 3H-thymidine incoporation. MC cell-cycle was analyzed by flow cytometry. Cyclin D1 and cyclin A expression was determined by Western blot analysis. Reactive oxygen species(ROS)production was measured by 2’,7’-dichlorofluorescein diacetate(DCFDA) fluorescence. Results:①ALDO-induced MC proliferation was inhibited by PPAR-酌 agonist rosiglitazone in dose-dependent manner in mouse mesangial cells; ②ALDO increased cell number in S- and G2/M phase,which was inhibited by rosiglitazone; ③Rosiglitazone reduced ALDO-induced cyclin D1 and cyclin A expression in dose-dependent manner; ④NAC significantly inhibited ALDO-induced MC proliferation. Rosiglitazone dose-dependently inhibited ALDO-induced ROS production. Conclusions:ROS involved in ALDO-induced MC proliferation. PPAR-酌 ligand rosiglitazone blocked ALDO-induced MC proliferation via inhibition of ROS production.