5种大黄游离蒽醌大鼠在体肠吸收的单向灌流法研究

Intestinal Absorption Kinetics of Rhubarb Mixture Free Anthraquinones in Rats

目的研究5种大黄游离蒽醌混合物(FAM,芦荟大黄素、大黄酚、大黄素、大黄酸、大黄素甲醚)在大鼠各肠段的吸收状况。方法运用大鼠在体单向灌流肠吸收模型,HPLC法测定灌流液中FAM的浓度,分别考察FAM中5种物质在十二指肠、空肠、回肠、结肠及胆汁引流十二指肠段的吸收速率常数(Ka)和药物表观吸收系数(Papp)。结果芦荟大黄素、大黄素和大黄酸主要吸收部位为十二指肠,大黄酚在十二指肠和结肠段的吸收均较大,大黄素甲醚主要吸收部位为结肠;各物质在回肠段的吸收速率均最低(P<0.05)。结论 FAM作为肠灌流液时,各物质的吸收与肠道的酸碱内环境和物质本身的脂溶性有关,同时可能存在相互间吸收的竞争与拮抗作用。胆汁对FAM在十二指肠的吸收有抑制作用。单向肠灌流实验表明FAM在各肠段吸收良好,这与体循环血液中除大黄酸外各物质测定浓度较低存在矛盾,推测这与相关物质的肠道代谢有关。

Objective To evaluate intestinal absorption characteristic of Rhubarb mixture free anthraquinones（Aloe-emodin,Rhein,Emodin,Physcion,Chrysophanol） in rats.Methods The rat single-pass intestinal perfusion technique was applied.The concentration of Rhubarb mixture free anthraquinones was determined in intestinal perfuse by HPLC to investigated absorption constant（Ka） and apparent absorption coefficient（Papp） of Rhubarb mixture free anthraquinones in duodenum jejunum ileum colon and drainage-bile of duodenum.Results In the small intestine,the specific absorption parts of aloe-emodin,emodin and rhein were in the duodenum;Chrysophanol had a larger absorption in duodenum and colon;Physcion of absorption in the colon segment was the strongest;Every material in the ileal absorption rate was the lowest（P0.05）.Conclusion Rhubarb mixture free anthraquinones of absorption is related to acid-base environment in intestine and fat-soluble of Rhubarb mixture free anthraquinones.Bile has an inhibitory effect on the absorption of Rhubarb mixture free anthraquinones,which suggests in duodenum.There are contradictions between absorption in different intestine segments and circulation bloods.It suggests that is may be related to substances intestinal metabolism.