Aim To study the function of amlodipine on cellular cholesterol accumulation and cyclophilin a expression in foam cells derived from smooth muscle cell induced by oxidized low density lipoprotein(ox-LDL) to explore the new antiatherosclerotic role of Amlodipine.Methods The experiment groups included 6 groups:control group,ox-LDL group,different concentration(0.1,1.0,10.0 μmol/L)of amlodipine pretreated for 1 h and treated with 80 mg/L ox-LDL for 72 h group and amlodipine treated alone without ox-LDL group.RT-PCR and Western-blot analysis were used to detect the mRNA and protein expression of cyclophilin A.Oil red O dye experiment showed the lipid droplets in the cells of each group.High Performance liquid chromatography(HPLC) analysis was peformed to measure the content of cellular total cholesterol and cholesterol ester.Results RT-PCR and Western-blot analysis showed that with ox-LDL and amlodipine treatment,cyclophilin A expression were greatly increased in a concentration-dependent manner.Oil Red O dye showed that with the treatment of amlodipine,the lipid droplets were greatly decreased in a concentration-dependent manner vs ox-LDL group.The content of cellular total cholesterol and cholesterol ester were both significantly increased with ox-LDL treatment but decreased after amlodipine treatment.Conclusion Amlodipine can up-regulate the expression of cyclophilin A and relieve the cellular cholesterol accumulation in foam cells derived from smooth muscle cells induced by ox-LDL.