摘要
目的:研究地西泮的在体肠吸收机理。方法:通过大鼠在体肠灌流和单向灌流模型,采用反相高效液相法测定药物浓度和油水分配系数,研究3种吸收促进剂Labrasol、Tween-80和十二烷基硫酸钠对地西泮肠吸收和转运的影响。结果:地西泮肠吸收速率与灌流液的pH值和肠段部位有关,地西泮为全肠段吸收,其中十二指肠和空肠的吸收速率较大,分别为(0.186±0.006)h-1和(0.170±0.011)h-1;回肠和结肠段吸收速率依次减小,分别为(0.086±0.023)h-1和(0.059±0.012)h-1。Labrasol和Tween-80可明显增加地西泮在小肠段的吸收速率。结论:地西泮的肠吸收机理为被动扩散,其吸收动力学符合一级过程。
Aim：To investigate the absorption mechanism of diazepam in various intestinal segments. Methods： In situ recirculation and single-pass perfusion were used to study the absorption mechanism of diazepam in rats. The concentrations of diazepam in intestinal fluid was measured by HPLC, and the oil-water partition coefficient of diazepam was caculated. The effects of three kinds of surfactants （Labrasol,Tween-80 and sodium dodecyl sulfate） on the absorption and transport of diazepam were also studied. Results：The absorption rate of diazepamwas obviously influenced by pH of regurgitation fluid and intestinal segments. Diazepam was absorbed in the whole intestine. The absorption rate constant （Ka） was greater in duodenum and jejunum. Ka in duodenum,jejunum, ileum and colon were estimated to be （0.186 ± 0.006）h^-1, （0.170 ± 0.011）h^-1, （0.086 ± 0.023） h^-1 and （0.059 ± 0.012）h^-1, respectively. Labrasol and Tween-80 evidently enhanced the absorption of diazepam in intestine. Conclusion： The absorption of diazepam occured via the simple diffusion.
出处
《中国药科大学学报》
CAS
CSCD
北大核心
2006年第6期507-511,共5页
Journal of China Pharmaceutical University
基金
国家高技术研究发展计划("八六三"计划)资助项目(No.2004AA2Z3020)~~
关键词
地西泮
在体肠灌流
单向灌流法
吸收促进剂
吸收动力学
油水分配系数
diazepam
in situ recirculation
single-pass perfusion
absorption enhancer
absorption-kinetics
oil-water partition coefficient
