Abstract: Objective： To explore the effect of peroxisome proliferators-activated receptor α on myocardial fibrosis induced by angiotensinⅡin vitro. Methods： Cardial fibroblasts (CFs) of neonatal Wistar rats were isolated and cultured, and were stimulated with AngⅡ. CFs proliferation was measured by thiazolyl blue（MTT）assay. mRNA was measured by reverse transcriptionpolymerase chain reaction(RT-PCR). Results： Compared with the control group, after a 12-hour treatment with AngⅡ, mRNA expression of collagen I and TIMP-1 in CFs was increased, but MMP-2 was significantly decreased while the MTT value of CFs was increased. Bezafibrate, a kind of PPARα activators， inhibited the above changes in a dose-dependent manner except for the MTT value, of which no significant changes were produced. MK886, a kind of PPARα antagon, abrogated the action of Bezafibrate. Conclusion： The results suggest that the PPAR αdependent pathway is critically involved in the inhibition of myocardial fibrosis in vitro.

Key words: Peroxisome proliferators, Transcription factors, Myocardial fibrosis