天麻素在大鼠体内的药动学研究

 目的研究天麻素在大鼠体内的药动学，探讨其在大鼠体内的动力学特征。方法采用胆管结扎术和颈静脉插管术，同时建立高效液相色谱法测定血浆中天麻素浓度的变化，应用3P87药动学程序对血药浓度数据进行拟合。结果天麻素在25～800 μg·mL^-1浓度范围内样品峰面积与内标峰面积比呈良好线性关系，其相关系数r=0.995。提取平均回收率83.6%，日内、日间RSD＜15%。大鼠静脉注射天麻素后体内药动学符合开放性双隔室模型，而灌胃给药符合开放性单隔室一级吸收模型，其绝对生物利用度为86.1%。大鼠结扎胆管前后AUC_0～180分别为(18±9)，(15±13) mg·min·mL^-1，经方差分析无显著性意义。结论天麻素在大鼠体内不存在肠肝循环。

Pharmacokinetics of gastrodin in rats

OBJECTIVE To study the pharmacokinetics of gastrodin in rats.METHOD S A permanent catheterization of jugular vein as well as bile duct ligation method was applied and a reversed phase high performance liquid chromatographic method was established for the determination of gastrodin in rat plasma.The data was processed with the software 3P87.RESULTS A good linearity was obtained from 25 μg·mL^-1 to 800μg·mL^-1 of gastrodin with a correlation coefficient of 0.995.The detection limit was 20μg·mL^-1.The extraction recovery was 83.6%.The RSD for the intra day and inter day were less than 15%.The concentration time profile after iv administration was found to be fitted to a two compartment open model,but the concentration time curve after ig was fitted to a one compartment open model.The absolute bioavailability was 86.1%.The AUC of groups before and after bile duct ligation were (18±9) and (15±13) mg·min·mL^-1,respectively.There was no significant difference.CONCLUSION The finding suggested that enterohepatic circulation of gastrodin did not exist in rats.