大鼠在体单向肠灌流模型研究肉桂酸肠道吸收特性

Study of intestinal absorption of cinnamic acid in one-way intestinal perfusion rat model

目的研究肉桂酸在大鼠肠道的吸收部位和吸收机制,以及转运蛋白对肉桂酸肠道吸收的影响。方法建立在体单向肠灌流模型,采用HPLC法测定肉桂酸在肠道中的浓度变化,通过吸收速度常数(Ka)和表观吸收系数(Peff)来研究肉桂酸的吸收动力学特征。结果肉桂酸在各个肠段的Ka和Peff结果为十二指肠>空肠>回肠,十二指肠和空肠的Ka和Peff值显著性高于回肠(P<0.05),不同浓度肉桂酸在同一肠段的Ka和Peff值差异无统计学意义,加入MRP2抑制剂(吲哚美辛)后Ka和Peff值差异亦无统计学意义,但加入Pgp抑制剂(盐酸维拉帕米)后其值则显著性增加。结论十二指肠、空肠是肉桂酸吸收的主要部位,吸收机制为被动转运,肠道转运受Pgp转运蛋白的影响,但不受MRP2转运蛋白的影响。

Objective To investigate the absorption characteristic of cinnamic acid in rat intestine and the influence of transporter protein on cinnamic acid absorption. Methods One-way intestinal perfusion rat model was established. HPLC was used to measure the content of cinnamon acid in intestine. The absorption rate constant （Ka） and the apparent absorption coefficient （Peff） were obtained to analyze the absorption kinetics of cinnamon acid. Results The values of Ka and Peff of cinnamic acid in three different regions of rat intestine showed duodenum 〉 jejunum 〉 ileum. The values of Ka and Pelf in the same region with different concentrations of cinnamic acid did not show a statistical difference. The values of Ka and Peff of cinnamic acid did not change when treated with MRP2 inhibitor （domethacin） in jejunum, but which significantly increased when treated with Pgp inhibitor （verapamil hydrochloride ） in duodenum. Conclusion Duodenum and jejunum may be the main sites of cinnamic acid absorption, by which mechanism is related to passive diffusion influenced by Pgp, but not MRP2.