目的 研究羥基積雪草苷在大鼠腸段各段的吸收特征，探究其在腸道的吸收機制，為設(shè)計藥物的劑型和給藥途徑提供理論基礎(chǔ)。方法 利用大鼠在體循環(huán)腸灌流模型和方法，探明羥基積雪草苷的腸道吸收部位和吸收特征，以及不同表面活性劑對其腸吸收的影響。結(jié)果/b> 羥基積雪草苷在大鼠小腸段吸收強于大腸段，其吸收速率回腸＞空腸≥十二指腸＞結(jié)腸。而不同濃度的羥基積雪草苷溶液回腸吸收率和吸收速率常數(shù)無顯著差異。在3種不同表面活性劑中，聚山梨酯-80對羥基積雪草苷的回腸吸收具有顯著的促進作用。結(jié)論 羥基積雪草苷的腸吸收主要集中在小腸中段，且吸收機制推測為被動擴散，表面活性劑聚山梨酯-80可以促進其回腸吸收。

Objective To investigate the absorptive characteristics of madecassoside in different intestinal segments of rats, to observe its intestinal absorption mechanism, and to provide rational foundation for its dosage form and administration route design. Methods In situ intestinal perfusion model was used to suudy the best absorptive site, absorptive characteristics, and transport behavior influenced by three different surfactants. Results The results showed that the absorption of madecassoside in small intestine was much higher than that in large intestine, and the rank order of intestinal permeability was ileum > jejunum > duodenum > colon; There was no significant difference of absorption parameters of madecassoside at various concentrations; Among three surfactanrs, Tween-80 could signifantly improve the intestinal absorption of madecassoside. Conclusion Main absorptive segments are middle site of small intestine, transport mechanism is similar to passive diffusion, and Tween-80 could enhance madecassoside absorption in ileum.