The Study On Quality Control For Yinchen And Pharmacokinetics Of Yinchenhao Decoction

In this paper, the study on pharmacokinetics of 6,7-dimethoxycoumarin in Yinchenhao Tang was reported. A reversed-phase high performance liquid chromatographic method was established for determination of 6,7-dimethoxycoumarin in rat plasma. The plasma concentrations and pharmacokinetic parameters of 6,7-dimethoxycoumarin were compared after vein administration of 6,7-dimethoxycoumarin and oral administration of 6,7-dimethoxycoumarin, Artemisiae Scopariae decoction, Artemisiae Scopariae decoction plus Rhizoma Rhei and Gardeniae decoction and Yinchenhao Tang respectively. The results showed that plasma concentration-time profile after oral administration of 6,7-dimethoxycoumarin was fitted in with two compartment model. The absolute bioavailability of 6,7-dimethoxycoumarin was calculated to be 79.5%. After oral administration of Artemisiae Scopariae decoction, the eliminative speed reduced more slowly than 6,7-dimethoxycoumarin. The AUC values increased significantly after oral administration of Artemisiae Scopariae decoction plus Rhizoma Rhei and Gardeniae decoction and Yinchenhao Tang compared with oral administrationof Artemisiae Scopariae decoction. These indicated that Rhizoma Rhei and Gardeniae could facilitate the absorption of 6,7-dimethoxycoumarin significantly in Yinchenhao Tang and enhance bioavailability of 6,7-dimethoxycoumarin. At the same time, metabolism of 6,7-dimethoxycoumarin were researched based on the study of pharmacokinetic, two metabolites were fmded by HPLC-MS", the metabolic rode was identified preliminary. In addition, the reversed-phase high performance liquid chromatographic methods were established for determination of Chlorogenic acid, p-hydroxy-acetophenone, 7-methylesculetin and 6,7-dimethoxycoumarin in Yinchen. The methods were accurate, precise and satisfactory for quality control of Chinese medicinal Artemisiae Scopariae and its prescriptions.