岩黄连生物碱在大鼠胃肠道的吸收动力学研究

目的:以脱氢卡维丁为指标成分研究岩黄连总生物碱在大鼠胃、肠的吸收动力学特征.方法:采用大鼠在体胃、肠吸收模型,以高效液相色谱法测定胃、肠灌注液中药物的含量.结果:药物在胃和小肠中的每小时吸收百分率分别为8.88%,2.08%;药物在大鼠十二指肠、空肠的吸收速率常数略高于回肠和结肠部位,但无显著性差异;药物中、高浓度的吸收速率常数基本一致,低浓度的吸收速率常数明显降低;随灌流液pH升高,药物吸收速率常数增大,但也无显著性差异.结论:药物在胃、全肠道均有吸收,但吸收均较差,胃中高于小肠中;不同肠段和灌流液不同pH对吸收无显著性影响;中、高浓度范围内表现为被动扩散吸收机制.

Absorption kinetics of dehydrocavidine in rats' stomachs and intestines

Objective: To study the absorption kinetics of dehydrocavidine in rats' stomachs and intestines.  Method: The absorption kinetics was investigated by the in situ perfusion in rats and the concentrations of drug perfusion solutions were determined by HPLC.  Result: The hourly absorption percentages of dehydrocavidine in stomach, small intestine were 8.88%, 2.08%, respectively. Although the absorption rate constants of dehydrocavidine in duodenum and jejunum are more than that in ileum and colon, there is no significance difference between them. The absorption rate constants kept at the same level when the concentrations of drug perfusion solution are at middle and high level. The increase of the pH of perfusion solution didn't significantly affect the absorption rate constants of the drug.  Conclusion: Dehydrocavidine was absorbed poorly at stomach and all segments of intestine in rats, but the absorptions in stomach are better than intestine. Dehydrocavidine was absorbed mainly via passive transport mechanism between middle and high concentration levels.