Effects of five drugs including ciclosporin and nifedipine which were usually used in patients with kidney transplantation on erythrocyte thiopurine methyltransferase activity / 中国临床药理学与治疗学

ABSTRACT

AIM:To investigate the effects of five drugs which were usually used simultaneously with aza- thioprine(AZA)in patients with kidney transplantation ciclosporin,hydrocortisone,nifedipine,captopril and al- lopurinol on erythrocyte thiopurine methyltransferase (TPMT)activity.METHODS:The erythrocyte TPMT activity of healthy volunteers was measured by high-per- formance liquid chromatography(HPLC).Sixteen volun- teers were chosen,in which 8 cases with intermediate TPMT activity and others with normal TPMT activity.The mean inhibition ratio of each drug concentration and the mean IC_(50)values of the inhibitors were determined.RE- SULTSCiclosporin,hydrocortisone,captopril and allo- purinol had nearly no impacts on TPMT activity.Nifedip- ine highly inhibited TPMT activity in vitro,the mean IC_(50)value in intermediate TPMT activity group was(24?17)?g/mL and in normal TPMT activity group was(12?10)?g/mL.CONCLUSION:The co-administration of nifedipine and thiopurines may lead to drug interactions.