Pharmacokinetics of lyophilized cataipol powder in rats

HE Yao; XUE Qiang; CHEN Hong; XU Xiao-yu

Abstract：Objective:To develop an HPLC method for the determination of catalpol in rat plasma,and determine the pharmacokinetics of lyophilized catalpol powder.Methods:Catalpol and its lyophilized powder (5.0 mg·kg-1) were injected through tail vein.The content of catalpol in plasma was measured by HPLC at 1,5,15,30,45,90,120,240,420,and 600 min after administration,respectively.Then,the pharmacokinetic parameters of catalpol were calculated by DAS 2.1 pharmacokinetic software.Results:After administration with lyophilized catalpol powder,the pharmacokinetics of catalpol was in accordance with two compartment model.The main pharmacokinetic parameters of lyophilized powder of catalpol are as follows:the t1/2α was (30.52 ± 5.81) min,t1/2 β was (182.25 ±36.32) min,Vc was (0.191 9 ±0.0162) L·kg-1,CL was (0.001 5 ±0.000 1) kg·L·min-1,and AUC was (3 451.66 ± 210.41) mg·min·mL-1,respectively.There were no significant differences between the parameters of the two preparations.Conclusion:After intravenous injection,the absorption and elimination of catalpol were in accordance with the feature of first order kinetics process.In addition,the pharmacokinetic feature of catalpol does not change in lyophilized catalpol powder.