异甘草素微乳改善大鼠小肠吸收的研究

 目的 研究异甘草素微乳（Iso-ME）对异甘草素（Iso）实验性小肠吸收的改善作用。方法 采用大鼠单向灌流模型和离体外翻肠囊模型研究异甘草素微乳在大鼠小肠的吸收行为。结果 大鼠在体小肠吸收实验中，异甘草素微乳可被大鼠全肠段吸收，在各肠段的K_a及P_app均高于异甘草素；各肠段K_a、P_app是结肠>回肠>十二指肠>空肠，结肠吸收最好 (P<0.01)。在4~16 μg·mL^-1内，异甘草素微乳在小肠的K_a不具有显著性差异。离体小肠吸收实验中，异甘草素微乳吸收量和吸收率较异甘草素分别提高34.45%和78.98%，肠壁通透性增加38.30%。在4~16 μg·mL^-1内，吸收符合Fick′s扩散定律，表现出一级动力学过程。结论 异甘草素微乳通过提高肠壁通透性一定程度地改善其吸收，在小肠的吸收主要以被动扩散方式吸收。

Enhanced Absorption of Isoliquiritigenin Microemulsion in Small Intestine of Rats

OBJECTIVE To investigate whether the absorption of isoliquiritigenin（Iso） can be enhanced by using isoliquiritigenin microemulsion (Iso-ME). METHODS The uptake and intestinal permeability of Iso solution and Iso-ME were determined by using single-pass intestinal perfusion model and reverted gut sac method. RESULTS The Iso in Iso-ME could be absorbed in the whole intestinal segments. The values of the absorption rate constants (K_a) and apparent permeability coefficients (P_app) of Iso-ME in different parts of intestine were in the following sequence colon>ileum>duodenum>jejunum； the K_a and P_app at colon were significantly higher than that at the other regions of intestine (P<0.01). The K_a of Iso-ME in intestine had no significant difference in the range of 4-16 μg·mL^-1.The uptake and absorption rate of Iso-ME increased 34.45% and 78.98%； the permeability coefficient increased 38.30% compared with Iso solution. The absorption process obeyed the Fick′s law in the range of 4-16 μg·mL^-1.CONCLUSION The Iso in Iso-ME is absorbed through passive diffusion， and the absorption is enhanced by increasing the permeability.