鸢尾苷元的大鼠在体肠吸收研究

In situ intestinal absorption of tectorigenin in rats

目的 研究鸢尾苷元在大鼠肠道内的吸收规律。方法 采用大鼠在体小肠循环灌流的方法,利用紫外分光光度法和HPLC法分别测定循环液中酚红和鸢尾苷元的浓度。研究鸢尾苷元在大鼠全肠段及十二指肠、空肠、回肠、结肠中的吸收情况。结果 鸢尾苷元可在大鼠小肠中吸收,低、中、高浓度的吸收速率常数Ka分别为0.0997±0.0177、0.1330±0.0190、0.1513±0.0134 h^（-1）;鸢尾苷元在十二指肠、空肠、回肠、结肠的吸收速率常数Ka分别为0.0657±0.0233、0.0576±9.6×10^（-3）、0.1778±0.0879、0.0809±0.0254 h^（-1）。按吸收速率常数由高到低排列为回肠〉结肠〉十二指肠≈空肠。结论 鸢尾苷元在大鼠小肠全段有不同程度的吸收,回肠可能为其主要吸收部位;鸢尾苷元在大鼠小肠中的吸收机制并非单纯的被动扩散,可能存在着载体介导的转运。

OBJECTIVE To investigate the in situ intestinal absorption behaviors of tectorigenin in rats. METHODS The in situ rat intestinal perfusion model was used, and the changes of tectorigenin and phenol concentration in the perfusate were determined by UV spectrophotometry and HPLC to study the absorption characteristics of tectorigenin in the whole intestine and four different intestinal segments. RESULTS Although tectorigenin was absorbed in the small intestine,it was poorly absorbed. The Ka of tectorigenin at low, medium and high concentration was 0. 0997± 0. 0177 h- 1,0. 1330 ± 0. 0190 h -1, and 0.1513 ±0. 0134 h - 1 , respectively. The Ka of tectorigenin in duodenum,jejunum, ileum and colon was 0. 0657 ±0. 0233 h-1, 0. 0576±9.6 × 10-3 h-1, 0. 1778 ± 0. 0879 h-1 and 0. 0809 ±0. 0254 h - 1, respectively. The Ka of teetorigenin in small intestine was in an order of ofileum 〉 colon 〉 duodenum jejunum. CONCLUSION There is a certain extent for tectorigenin absorption in the whole small intestine and the ileum is probably the main site. The mechanism of tectorigcnin absorption in rat small intestine is not solely passive diffusion, there may be a carrier mediated transport.