Pharmacokinetics Of Paeoniflorin In Dogs And Rats

Objective: A high performance liquid chromatograph (HPLC) method for analyzing the concentration of paeoniflorin(PF) in plasma was established. And the aim of this study was to compare the pharmacokinetics (PK) parameters of total glucosides of paeony(TGP) and PF intravenous injected in healthy rats and in rats with adjuvant arthritis(AA).Methods: The HPLC assay was established by Hypersil C₁₈ column (4.6mm×250mm, 5μm) with methanol-water(40:60) as mobile phase at a flow rate of 0.8mL·min^-1.The detection wavelength was UV 230nm.20μL of sample was injected into the C₁₈ column where the temperature was 30℃.The plasma sample was extracted with acetoacetate for HPLC analysis. Plasma sample were collected at different time to construct pharmacokinetic profiles by plotting drug concentration versus time after intravenous administration of TGP in healthy dogs, intravenous administration of PF and TGP in healthy rats or in rats with AA.The plasma concentration-time curve and the pharmacokinetic parameters were calculated with DAS ver 2.0 practical pharmacokinetics program.Results: 1. The linearity range for PF in plasma in dogs was obtained from 0.025μg·mL^-1 to 25.00μg·mL^-1 and the linear regression equation was y = 98119x +3995.9(R² = 0.9987, 0.025- 1μg·mL^-1) and y=107389x-25730(R²=0.9994, 1-25μg·mL^-1).The limits of detection for PF was 0.025μg·mL^-1. The recoveries was more than 90%(n=5), The relative standard deviations of the intra-day and inter-day...