鞣花酸大鼠在体肠吸收研究

In situ intestinal absorption of ellagic acid in rats

目的：探讨鞣花酸在大鼠不同肠段的吸收动力学特征及吸收机制。方法：采用大鼠在体小肠单向灌流实验模型，以高效液相色谱法测定鞣花酸药物浓度，分别研究不同药物浓度，不同吸收部位对鞣花酸大鼠肠吸收的影响。结果：鞣花酸在6～18μg·ml^-1内时，相同肠段在不同浓度，吸收速率常数（K9）及有效渗透系数（Peff）差异无显著性（P〉0．05）；不同肠段在相同浓度，结肠Ka及Peff差异有显著性（P〈0．05），为特异性吸收，其他3个肠段差异无显著性；鞣花酸的Peff〉1．2×10^-3cm·min^-1，表明其属于高渗透性药物。结论：鞣花酸浓度对Ka及Peff无显著性影响；鞣花酸的肠道最佳吸收部位为结肠；鞣花酸在大鼠肠道的吸收机制为被动扩散。

OBJECTIVE To determine the absorption characteristics and absorption mechanism of ellagic acid at various intestinal segments of rats. METHODS Single-pass intestinal perfusion technique was used to study the intestinal absorption of ellagic acid in different segments and different drug concentration, concentration of ellagic acid in samples was determined by HPLC. RESULTS When the drug concentration of ellagic acid was in 6 - 18 g·ml^-1 , in the same bowel segment, Ka and Peff, had no significant difference in the different concentration （P〈0. 05） ; in the same concentration, the Ka and Pelf in colon bad significant difference （P〈0. 05） in the different intestine, it was called specific absorption, the other three bowel segments had no significant difference. When the Pelf which was in ellagic acid〉 1.2× 10^-3 cm. min^-1, indicated that it was a kind of high permeability of drugs. CI）NCLUSION Concentration of ellagic acid has no significant effect on its absorption kinetics. The best absorption segment of the bowel was colon. The absorption of ellagic acid in the intestine is a passive diffusion mechanism.