Expression of peroxisome proliferator-activated receptor gamma (PPARgamma) in rat aortic smooth muscle cells

Peroxisome proliferator-activated receptor gamma (PPARgamma), a member of nuclear receptors, is expressed at a high level in adipose tissue and plays an important role in adipocyte differentiation. In the present study, we identified the expression of PPARgamma in rat aortic smooth muscle cells (RASMC) using reverse transcription-polymerase chain reaction and gel mobility shift assay. In addition, to investigate whether PPARgamma in RASMC is functional or not, we examined the effect of two specific ligands for PPARgamma, a thiazolidinedione anti-diabetic agent, troglitazone, and 15-deoxy-Delta12,14-prostaglandin J2, on the transcriptional activity of PPAR responsive element (PPRE). A significant increase in the activity of PPRE by addition of these ligands was found. These results suggest that in RASMC, target genes for PPARgamma may be activated by specific ligands for PPARgamma through PPRE in their promoters. In conclusion, PPARgamma is expressed and functional in vascular smooth muscle cells.