Cocktail 探针药物法评价辣椒素对大鼠CYP450亚型的影响

目的：采用cocktail 探针药物法研究辣椒素在体外对大鼠肝微粒体CYP 450四种亚型的影响。方法：分为试验组和对照组,试验组采用大鼠肝微粒体孵育体系、探针药物和系列浓度的辣椒素（对照组仅加入缓冲液）共同孵育20 min,反应终止后用HPLC方法检测代谢产物的生成量以代表酶的活性。采用Graphpad prism 5.0计算辣椒素对各亚型的IC50值。将辣椒素与大鼠肝微粒体分别预孵育0,5,10,15,20,30 min,计算不同预孵育时间下各亚型的相对活性百分比。结果：辣椒素对大鼠肝微粒体CYP1A2、CYP2C11、CYP2E1和CYP3A2的IC50值分别为36.21,17.19,51.64,18.86μmol·L-1。预孵育没有增强辣椒素对CYP450的抑制作用。结论：辣椒素在体外对大鼠肝微粒CYP1A2、CYP2C11、CYP2E1和CYP3A2具有抑制作用,且未呈现出预孵育时间依赖性。

Effects of Capsaicin on Rat Cytochrome P450 Isoforms by Cocktail Probe Drug Method

Objective：To investigate the in vitro effect of capsaicin on four major rat cytochrome P450 （ CYP） enzymes using a cocktail probe drug method. Methods：The in vitro incubation was divided into capsaicin group and the control group. Rat liver micro-somes, probe drugs, capsaicin at various concentration （ buffer solution in the control group） and cofactors were cultured altogether for 20 min. After the culture, the concentration of metabolites was determined by HPLC to assess the activities of enzymes. IC50 value of capsaicin on every isoform was calculated using Graphpad prism 5. 0. Capsaicin and hepatic microsomess were pre-incubated respec-tively for 0, 5, 10, 15, 20 and 30 min, and then the relative activity of the four isoforms at different time was calculated. Results：The activity of the rat liver microsomes enzyme CYP450 isoforms （CYP1A2, CYP2C11, CYP2E1 and CYP3A2） was all inhibited by capsaicin in vitro with IC50 value of 36. 21, 17. 19, 51. 64 and 18. 86 μmol·L-1 , respectively. Pre-incubation could not increase cap-saicin inhibitory activity against the four CYP enzymes. Conclusion：Capsaicin shows inhibition on CYP1A2, CYP2C11, CYP2E1 and CYP3A2 in rat liver microsomes in vitro without pre-incubation time-dependent property.