目的 研究甘草黄酮类成分对Caco-2细胞P-糖蛋白（P-gp）功能和表达的影响，探讨甘草解毒的作用机制。方法 采用流式细胞仪检测经甘草黄酮类成分处理后Caco-2细胞对罗丹明123摄取量的影响，以评价P-gp的外排功能；采用Western blotting法检测甘草黄酮类成分对Caco-2细胞P-gp表达的影响。结果 与对照组相比，甘草总黄酮5、10、50、100 μg/mL作用Caco-2细胞1 h后，使细胞内罗丹明123的荧光强度分别减少61.1%、56.3%、49.2%、45.4%；甘草苷、异甘草苷、甘草素、异甘草素、芹糖基甘草苷、芹糖基异甘草苷在相同质量浓度，使细胞内罗丹明123的荧光强度减少了19.3%～37.9%。与对照组相比，甘草总黄酮10～400 μg/mL给药后72 h，使Caco-2细胞膜上P-gp的表达显著增加（P＜0.01）；甘草苷、异甘草苷、甘草素、芹糖基甘草苷5～400 μmol/L，异甘草素、芹糖基异甘草苷10～400 μmol/L对此也有显著作用（P＜0.01）。结论 甘草黄酮类成分增强Caco-2细胞P-gp的功能，上调P-gp的表达，促进细胞内有毒物质的外排，减少有毒物质在肠道的吸收，这可能是甘草配伍其他中药的解毒机制之一。

Objective To study the effects of the flavonoids from Glycyrrhizae Radix (FGR) on the function and expression of P-glycoprotein (P-gp) in Caco-2 cells, and to further explore the detoxification mechanisms of FGR. Methods Flow cytometry was used to study the effects of FGR on the uptake of Rhodamine 123, which showed the toxic efflux function of P-gp; Western blotting method was used to detect the expression level of P-gp in Caco-2 cells. Results Compared with the control group, after treated with the total flavonoids from Glycyrrhizae Radix (TFGR) at the different concentration (5, 10, 50, and 100 μg/mL) for 1 h, the uptake of Rhodamine 123 in Caco-2 cells was decreased by 61.1%, 56.3%, 49.2%, and 45.4%; liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, liquiritin apioside, and isoliquiritin apioside with the same dose significantly decreased the fluorescence intensity of Rhodamine 123 by 19.3%—37.9%. The expression levels of P-gp in Caco-2 cells were significantly increased (P < 0.01) after the co-incubation of TFGR (10—400 μg/mL) for 72 h, and liquiritin, isoliquiritin, liquiritigenin, and liquiritin apioside (5—400 μmol/L) had the similar functions, so did isoliquiritin and isoliquiritin apioside (10—400 μg/mL, P < 0.01). Conclusion FGR could strengthen the function, up-regulate the expression of P-gp in Caco-2 cells, promote the efflux of toxic substances, and decrease the absorption of toxic substances, which could be one of the new mechanisms for Glycyrrhizae Radix detoxification.