ABSTRACT
Objective To study the effects of traditional Chinese medicine Panax notoginoside(PNS,血塞通) and Tetramethylpyrazine(TMPz,川芎嗪) on different subtypes of cytochrome P450(CYP450),based on that,to forecast the inter-reaction between these two drugs and between each one of them and another drug,and also to estimate the safety assessment of them.Methods The metabolic changes of caffeine and dapsone which are the specific probe drugs for subtypes of CYP450,CYP1A2 and CYP3A4,were studied in vitro to estimate the inhibition or induction effects of PNS and TMPz.Results The concentrations of caffeine and dapsone,the probe drugs in liver cytochrome P450,in control group,PNS group and TMPz group were all declined with time prolongation,and there were no significant differences among the three groups.The half life time(t1/2) of caffeine in PNS group was obviously shorter than that in control group((19.24?2.37) minutes vs.(25.15?2.02) minutes, P0.05).It was suggested that TMPz have no effect on both CYP1A2 and CYP3A4.Conclusion Different drugs have different effects on different CYP450 subtype enzymes.When PNS is used in combination with other drugs which are related to the metabolism of CYP1A2 enzyme,its induction effect on CYP1A2 should be considered fully to avoid toxic effect or the potential adverse reactions.