目的 研究马钱子碱、士的宁在MDCK-MDR1单层细胞模型中的双向转运机制。方法 MTT法确定马钱子碱、士的宁对MDCK-MDR1单层细胞毒性范围，以MDCK-MDR1单层细胞为体外研究模型，考察转运时间、药物作用质量浓度、P-糖蛋白（P-gp）抑制剂维拉帕米对马钱子碱、士的宁的累积吸收浓度（C_cum）和表观渗透系数（P_app）的影响。结果 马钱子碱和士的宁P_app均 > 1×10^-5 cm/s，P_{app（BL→AP）}/P_{app（AP→BL）}均<2。马钱子碱、士的宁与维拉帕米合用，显著降低了P_{app（BL→AP）}/P_{app（AP→BL）}值。结论 马钱子碱、士的宁以被动转运为主，P-gp抑制剂维拉帕米对其吸收有明显抑制作用，马钱子碱、士的宁可能是P-gp底物。

Objective To study the bi-direction transport behavior of brucine and strychnine in the MDCK-MDR1 cell monolayer model. Methods MTT method was employed to confirm the safe concentration of brucine and strychnine towards MDCK-MDR1 cells. The effects of transport time, drug concentration, and P-glycoprotein inhibitor verapamil on cumulative absorption concentration (Ccum) and apparent permeability coefficient (P_app) of brucine and strychnine in MDCK-MDR1 monolayer cells were studied. Results The P_app value of brucine and strychnine was larger than 1×10^-5 cm/s and the ratio of P_app(BL→AP) vs P_app(AP→BL) was less than 2. Brucine/strychnine combined with verapamil decreased the ratio of P_app(BL→AP) vs P_app(AP→BL). Conclusion The absorption of brucine and strychnine in MDCK-MDR1 cell monolayer model was well and the passive transference was its main intestinal absorption mechanism. The P-gp inhibitor verapamil has a significant inhibitory effect on brucine and strychnine absorption. Brucine and strychnine may be a substrate of P-glycoprotein.

R285.61

国家自然科学基金资助项目（81760717）；国家自然科学基金资助项目（81460606）；江西省中药学一流学科专项科研基金项目（JXSYLXK-ZHYAO048）