沙棘总黄酮的大鼠肠吸收特性考察

目的:考察沙棘总黄酮在大鼠小肠的吸收特性.方法:运用大鼠在体单向灌流和离体外翻肠囊模型,采用HPLC测定槲皮素、山奈酚、异鼠李素含量,计算沙棘总黄酮在大鼠小肠的吸收参数.结果:沙棘总黄酮中槲皮素、山奈酚、异鼠李素的最佳吸收部位分别为回肠、回肠、十二指肠,吸收速率常数(Ka)分别为3.405×10-2,3.649×10-2,5.671×10-2,沙棘总黄酮质量浓度在50 ～200 mg·L-1时,Ka和表观吸收系数无显著性差异.累积吸收量随药物质量浓度升高呈线性增加.结论:沙棘提取物中3种黄酮类成分均呈现一级动力学特征,吸收机制均为被动扩散,且在小肠有特定吸收部位.

Investigation of Rat Intestinal Absorption Properties of Total Flavonoids from Hippophae Fructus

Objective: To investigate rat intestinal absorption characteristics of total flavonoids from Hippophae Fructus. Method: In vitro everted gut sac model and in situ rat single-pass perfusion model were adopted,the contents of quercetin,kaempferol and isorhamnetin were determined by HPLC,rat intestinal absorption parameters of total flavonoids from Hippophae Fructus were calculated. Result: The best absorption parts of quercetin,kaempferol,isorhamnetin was ileum,ileum and duodenum,respectively.Absorption rate constant (Ka) of these three ingredients were 3.405×10^-2,3.649×10^-2,5.671×10^-2,respectively.Ka and apparent absorption coefficient had no significant difference when the concentration of total flavonoids from Hippophae Fructus was 50-200 mg·L^-1.A positive correlation was found between drug concentration and accumulated absorption amount. Conclusion: Absorption characteristics of these three main flavonoids components were consistent,all complied with the first order absorption kinetics,absorption mechanisms of them were passive diffusion,and they had specific absorption site in small intestine.