Objective    To observe the effect of peroxisome proliferators activated receptor gamma (PPAR-γ) on phenotypic transforming of vascular smooth muscle cells (VSMC) in hypertension.     Methods    Spontaneous hypertension rats (SHR) and WKY rats both aged 4 months were included. SHR rats as well as WKY rats were divided to be fed with normal chow

and chow added with rosiglitazone (10 mg·kg

-1

·d

-1

) for 16 weeks. VSMC were isolated from SHR rats and WKY rats and cultured by patch-attaching method

then respectively divided into 3 groups after treated with genetic r

ecombination technology: normal VSMC

PPARγ overexpressed VSMC and PPARγ silenced VSMC. Expressions of OPN and α-SMA

which respectively represent the undifferentiated and differentiated VSMC

were detected by Western blotting. Cell proliferation was determined by detecting DNA synthesis and cell counting. The changes of arteries were evaluated pathologically.     Results    Rosiglitazone decreased blood pressure and ameliorated vascular remodeling of aorta in SHR rats. Aorta of SHR showed an upregulation of OPN and downregulation of α-SMA

which could be inhibited by rosiglitazone. VSMC from SHR rats showed an upregulation of OPN and downregulation of α-SMA

and increased cell proliferation. These changes were all inhibited by rosiglitazone. In the cells that overexpressed PPARγ

the cell proliferation rate was lower

and the expressions of OPN and α-SMA were depressed

compared with the corresponding control cells.      Conclusion    PPAR-γ could inhibit the phenotypic transforming of VSMC

and this might be responsible for the amelioration of vascular remodeling in hypertension.