大鼠原位灌注模型研究靛玉红吸收机制

 目的研究靛玉红在大鼠肠道的吸收动力学特征,并考察不同药物浓度和增溶方法对其吸收速率的影响。方法选用适当增溶剂提高靛玉红的溶解度,进行大鼠原位肠灌注实验。结果靛玉红吸收较差,在4～16mg·L^-1内靛玉红的K_a值基本保持不变。各部位吸收速率依次为十二指肠≈回肠>结肠>空肠。尽管是否结扎胆管对吸收参数影响不大,但未结扎胆管时,小肠全肠段和十二指循环液的剩余药量-时间曲线波动较大,结扎胆管后波动明显减弱。结论在实验剂量范围内,靛玉红在大鼠肠道内的吸收呈现一级吸收动力学特征,其吸收机制为被动扩散,并可能存在肠肝循环。

Absorption Mechanism of Indirubin in Rat in Situ

OBJECTIVE To investigate the absorption kinetics of indirubin at different intestinal segments of rats.METHODS An in situ gut perfusion model was employed to investigate the absorptive kinetics of indirubin,after the solubilizer was used to increase its solubility.RESULTS Indirubin was poorly absorbed,and the permeability coefficient of indirubin was not effected by indirubin at the range from 4 to 16 mg·L^-1 in perfusate.The absorptive rate constants(K_a)of indirubin were 0.086,0,0.077,0.046 h^-1 at duodenum,jejunal,ileum and colon,respectively.Ligating bile duct showed no influence on the lnX-t curves,although no significant difference was investigated on permeability coefficients of indirubin.CONCLUSION The absorption of indirubin is a first-order process with the passive diffusion mechanism.Furthermore,there may existed enterohepatic cycle in rat absorption process.