Studies On Chiral Pharmacokinetics Of Tetrahydropalmatine And The Effect Of Yuanhu-Baizhi Combination

Tetrahydropalmatine (dl-THP) is a biologically active ingredient in a Chinese herb prescription named Yuanhu-Baizhi. This paper has focused on the enantiomeric separation and chiral pharmacokinetics of THP in animals, using a chiral HPLC method coupled with achiral column. The stereo selective disposition kinetics, such as plasma pharmacokinetics and excretion, of THP enantiomers in rats after an oral dose of the racemate was revealed for the first time. The concentrations of THP enantiomers in plasma, cortex, cerebellum, diencephalon, brain stem, striatum and hippocampus were measured and the striatum displayed significantly higher concentrations. The effects of the ingredients in Yuanhu-Baizhi prescription on the pharmacokinetics of THP enantiomers were also studied. The results of this thesis provided theoretical basis and techniques for further studies on tetrahydroprotoberberines. It was suggested that the pharmacokinetics of Chinese medicines could be used as an effective way of seeking inherent law of complex prescription principle.