Pharmacokinetics Of Paeoniflorin In Paeoniae Radix Extract In Rat And Effects Of Paeoniae Radix Extract On Monoamine Neurotransmitters In Cortex, Hippocampus And Striatum Of Rat Brain

In the present paper, the pharmacokinetics of paeoniflorin (PF) in Paeoniae Radix extract (PRE) was investigated in normal and cerebral ischemia-reperfusion rats, and the effects of PRE on monoamine neurotransmitters in specific brain region of rats were also investigated after intravenous administration of PRE. In addition, the pilot effects of PRE on depression in various mice depression model were investigated after oral administration of PRE. The main results are as follows:1. Dynamic changes of PF in plasma of normal and ischemia-reperfusion ratsIn this part, the cerebral ischemia-reperfusion rat model was induced by occluding bilateral carotid arteries of normal rat for 2 h, followed by reperfusion. The normal and model animals were divided into two groups according to different dose of PRE. The model rats were immediately administrated by PRE (at a dose of 60 mg·kg^-1 and 15 mg·kg^-1 of PF, respectively) via femoral vein at the same time of reperfusion; the normal rats were administrated at the same dose. Plasma samples were collected at different time to construct pharmacokinetics profiles by plotting drug concentration vs. time. Quantification of PF in rat plasma was achieved by using a simple and rapid high-performance liquid chromatographic (HPLC) method. In normal rats at a dose of 60 mg-kg^-1 of PF, the major parameters of distribution half-life (t_1/2α, elimination half-life (t_1/2β), area under the plasma concentration-time (AUC), mean retention time (MRT), and clearance (CL), estimated by an open two-compartmental model, were 0.69 min, 18.77 min, 5338.71 (μg·min)/ml,...