在体单向肠灌流模型研究千金子甾醇在大鼠肠吸收特性

目的：研究千金子甾醇在大鼠肠道内的吸收情况以及P-糖蛋白（ P-gp）和多药耐药相关蛋白（ MRP2）对千金子甾醇肠吸收的影响。方法采用大鼠在体单向肠灌流模型，运用高效液相色谱法测定十二指肠、空肠、回肠、结肠灌流液中千金子甾醇的含量，计算吸收速率常数（ Ka ）和表观渗透系数（Papp）。结果千金子甾醇在大鼠结肠的Ka 及Papp最高（P＜0．05）。加入P-gp抑制剂盐酸维拉帕米后，千金子甾醇在结肠段的Ka 及Papp显著增加；而加入MRP2抑制剂吲哚美辛后，千金子甾醇在大鼠结肠段的Ka及Papp普遍降低。结论千金子甾醇在肠道中的主要吸收部位为结肠，推测千金子甾醇可能为P-gp的底物，而非MRP2的底物。

Characteristic of intestinal absorption of euphorbia factor L1 by rats single pass intestinal perfusion moder in situ

Objective To study the characteristic of absorption of euphorbia factor L1 in intestine of rats, and to observe the effects of P-glycoprotein(P-gp)and multidrug resistance-associated protein(MRP2)on intestinal absorption of euphorbia factor L1 .Methods The contents of euphorbia factor L1 of intestinal perfusion fluid of duodenum, jejunum, ileum and colon in the rats in situ single-pass intestinal perfusion model were determined by using HPLC.The drug absorption rate constant( Ka ) and the apparent absorp-tion coefficient( Papp ) in four intestinal regions were calculated.Results Ka and Papp of euphorbia factor L1 at colon were the highest of the whole rat intestine.Significant increase of Ka and Papp showed at rat colon when co-perfused with verapamil hydrochloride, by contrast, decrease of Ka and Papp found when co-perfused with indomethacin.Conclusion We inferred that verapamil hydrochloride be the substrate of P-gp and that indomethacin be not the substrate of MRP2 .