Aim To study the effect of amlodipine on platelet-derived growth factor-B(PDGF-B) mRNA expression in HUVEC-12 endothelial cells induced by oxidized low density lipoprotein(ox-LDL) to explore the new antiatherosclerotic role of amlodipine.Methods HUVEC-12 endothelial cells were treated with 50 mg/L ox-LDL for 24 hours through the preexperiment.The experiment groups included 5 groups: control group,ox-LDL group,different concentration(0.1,1.0 and 10.0μmol/L) of amlodipine pretreated for 0.5 h and treated with 50 mg/L ox-LDL for 24 h group.RT-PCR was used to detect the mRNA expression of PDGF-B.Results RT-PCR analysis showed that with ox-LDL and amlodipine treatment,the mRNA expression of PDGF-B was greatly decreased in a concentration-dependent manner.Conclusion Ox-LDL can affect the mRNA expression of PDGF-B in the HUVEC-12 endothelial cells.Amlodipine can down-regulate the mRNA expression of PDGF-B.