Aim The effects of API0134 on expression of c-sis mRNA and platelet-derived growth factor B chain protein(PDGF-B)in porcine aortic endothelial cells (EC)induced by oxygen free radical (OFR) were studied in this article.Methods Immunohistochemistry,in situ hybridization and computer image analysis methods were used.Results The results showed,that OFR induces csis mRNA transcription and stimulates PDGF-B expression in EC;The inducible effects of OFR can be inhibited by API0134,the inhibitory effects are dose dependent.Conclusion These data suggest that API0134 may play a role in anti-atherosclerosis.