HPLC法测定大鼠血浆中雷公藤内酯醇及其药代动力学研究

Determination of plasma concentration of triptolide by HPLC and its pharmacokinetics after intravenous administration in rats

目的：建立大鼠血浆中雷公藤内酯醇的HPLC测定法，测定大鼠尾静脉注射雷公藤内酯醇后的血药浓度，并对其药代动力学进行评价。方法：血浆样品加入适量HCl后用乙酸乙酯提取进行HPLC分析，流动相为乙腈-水（23：77），流速为1．0ml／min，检测波长为217nm。大鼠尾静脉注射100μg/kg、200μg/kg、300μg/kg的三个剂量雷公藤内酯醇后，测定血浆中不同时间点雷公藤内酯醇的浓度，并计算主要药动学参数。结果：血浆中雷公藤内酯醇在0．02～10．0μg/ml浓度范围内线性关系良好，血浆中雷公藤内酯醇的最低检测线为0．02μg／ml，平均回收率为88．03％，日内和日间差异RSD均小于5％，峰面积与血药浓度呈良好的线性关系（r2=0．9993）。大鼠尾静脉分别注射三个剂量雷公藤内酯醇后，各剂量纽相对应的分布相（t1／2α）半衰期分别为：0．033，0．021，0.026h。消除相半衰期（t1／2β）分别为：0．753，0．630，0．574h。结论：本实验方法简便，可靠，可用于雷公藤内酯醇血药浓度分析及其药代动力学研究，测定结果可为该药的临床用药提供依据。

Objectives： To develop a high performance liquid chromatographic （ HPLC ） assay for determination of triptolide in rats plasma and to study the pharmacokinetics of triptolide in rats. Method： The plasma samples were extracted by ethyl acetate and seperated by a C18 reversed-phase column. The acetonitrile and the purified water composed mobile phase. The flow rate was 1.0 ml/min, ultraviolet detection wavelength was at 217 nm. Result： The calibration curve was linear over the range from 0. 02 - 10.0 μg/ml with a correlation coefficiency of 0. 9993. The lower limit of quantitation （LLOQ） was 0. 02 μg/ml. The mean recovery was 88.03%. The relative standard deviation （RSD） of intra-day and inter-day were all less than 15%. After intravenous administration of triptolide with 3 dosages of 100, 200, 300 μg/kg to rats, the corresponding distribution half-lives （t1/2α） were 0. 033, 0. 021, 0. 026 h, and the elimination half-lives （tl/213） were 0. 753, 0. 630, 0. 574 h, respectively. Conclution： This method is convenient, accurate and reliable. It can be used for determination of triptolide in rats plasma and pharmacokinetic studies.