石杉碱甲大鼠在体肠吸收动力学研究

目的研究石杉碱甲在大鼠小肠及各肠段的吸收动力学特征.方法采用大鼠在体方式对石杉碱甲进行了大鼠小肠及各肠段的吸收动力学研究;采用HPLC法测定石杉碱甲在大鼠体内肠吸收循环液中的药物浓度;采用UV法测定循环液中酚红浓度.结果石杉碱甲在小肠中吸收较好且没有特定吸收部位,各肠段吸收速率按十二指肠、空肠、回肠、结肠依次为0.001 0、0.000 9、0.001 1、0.000 9 h-1.结论结肠的吸收速率常数与小肠段相近,药物在肠道的吸收呈现一级吸收动力学,吸收机制为被动吸收,提示适于制备日服一次(24 h)缓释给药制剂.

Intestine absorption kinetics of huperzine A in rats

OBJECTIVE To determine the absorption of huperzine A in various intestine segments in rats.METHODS The absorption kinetics were obtained by the in situ perfusion method in rats. The concentration of huperzine A in intestine perfusate was measured by HPLC, and the concentration of phenolsulfonphthalein in intestine perfusate was measured by UV. RESULTS Huperzine A was steadily absorbed with the absorption rate constants at duodenum, jejunum, ileum and colon of 0. 001 0, 0. 000 9, 0. 001 1, and 0. 000 9 h^-1 , respectively. CONCLUSIONS The absorption of huperzine A complied with the passive transport mechanism and first order kinetics, suggesting that huperzine A could be designed as a 24 h-sustained-release dosage form.