尼扎替丁在大鼠体肠吸收动力学研究

目的研究尼扎替丁在大鼠肠道中的吸收机理。方法运用大鼠原位肠灌注模型，采用高效液相色谱法测定肠灌注液中药物和酚红的浓度，计算尼扎替丁在各部位的吸收参数。结果尼扎替丁在全肠段均有吸收，但吸收都较差，吸收速率常数为十二指肠〉回肠〉空肠〉结肠，不同浓度尼扎替丁循环时，吸收参数无统计学差异。结论尼扎替丁在大鼠肠道内的吸收呈现一级吸收动力学特征，其吸收机理为被动扩散。

The Study of Absorption Mechanism of Nizatidine in Intestine of Rat

Objective To study the absorption mechanism of Nizatidine in intestine of rats. Methods The model of in situ intestinal perfusion was applied in this research and HPLC method was established to determine the concentration of Nizatidine and phenolsulfonphthalein in the perfusate in order to calculate the absorption parameter of Nizatidine. Results Nizatidine was poorly absorbed, and the comparison of K, in different segments is as follows., duodenum〉ileum〉jejunal〉colon. There was no significant difference of absorption parameters. Conclusion Nizatidine complied with the first order absorption kinetics and the absorption mechanism of Nizatidine is passive transport.