中文摘要：

目的：研究紫草素微乳（Skn-ME）对紫草素（Skn）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,紫外分光光度法测定肠灌流液中紫草素的浓度变化,研究紫草素微乳在大鼠小肠的吸收部位和吸收动力学特征。结果：大鼠在体小肠吸收实验中,紫草素微乳可被大鼠全肠段吸收,在十二指肠、空肠回肠及结肠各肠段的药物吸收速率常数（Ka）分别是0.213 4,0.221 8,0.217 6,0.221 1 min-1;药物表观吸收系数（Papp）分别是0.035 69,0.036 37,0.036 32,0.037 27 cm.min-1,结肠段吸收最好（P〈0.001）。在15～60 mg.L-1内,紫草素微乳在小肠的Ka不具有显著性差异。离体小肠吸收实验中,紫草素微乳吸收量和吸收率较紫草素提高106.1%,肠壁通透性增加123.02%。在15～60 mg.L-1内,吸收符合Fick’s扩散定律,表现出一级动力学过程。结论：紫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。

英文摘要：

Objective：To investigate whether the absorption of shikonin can be enhanced by using shikonin microemulsion.Method： The uptake and intestinal permeability of shikonin and shikonin microemulsion were observed by using single-pass intestinal perfusion model and reverted gut sac method.Result：The shikonin microemulsion could be absorbed in whole intestinal segments.The absorption rate constants（Ka） of shikonin microemulsion at duodenum,jejunum,ileum and colon was 0.213 4,0.221 8,0.217 6,0.221 1 min-1,respectively;the apparent permeability coefficients（Papp） of was 0.035 69,0.036 37,0.036 32,0.037 27 cm·min-1.Ka and Papp at colon were significantly higher than that at the other regions of intestine（P0.001）.Ka of shikonin microemulsion in intestine had no significant difference in the range of 15-60 mg·L-1.The uptake and absorption rate of shikonin microemulsion increased with 106.1%;the permeability coefficient with 123.02%.The absorption process obeyed the Fick＇s law in the range of 15-60 mg·L-1.Conclusion：The absorption shikonin microemulsion is enhanced by increasing the permeability through a passive mechanism.