Comparative HPLC-MS/MS-based pharmacokinetic studies of multiple diterpenoid alkaloids following the administration of Zhenwu Tang and Radix Aconiti Lateralis Praeparata extracts to rats.

Abstracts Zhenwu Tang (ZWT) is a traditional Chinese medicine that is primarily composed of Radix Aconiti Lateralis Praeparata (FZ) and diterpenoid alkaloids are believed to be the pharmacologically active compounds of ZWT. In this study, the pharmacokinetic profiles of hypaconitine, mesaconitine, aconitine, benzoylmesaconitine, benzoylaconitine, and benzoylhypacoitine were assessed in rats following intragastric ZWT administration. Furthermore, differences in the pharmacokinetic profiles of these six alkaloids were assessed as a function of rat sex and the administration of ZWT or FZ extracts to these animals. Plasma levels of these alkaloids were quantified via HPLC-MS/MS. Significant differences in key pharmacokinetic parameters were observed when comparing rats administered FZ or ZWT. Relative to FZ extract treatment, ZWT administration was associated with Cmax and AUC0-∞ values of benzoylmesaconitine that were about 3.5 and 5.5 times higher. Considerable variations in hypaconitine pharmacokinetic parameters were also revealed between female and male rats. The Cmax and AUC0-∞ of hypaconitine were about 2.5- and 2.7-fold elevated in female rats in comparison with male rats. These results suggested that the other compounds within ZWT can enhance the absorption of benzoylmesaconitine, while hypaconitine exhibits higher bioavailability in female rats, as compared with male rats.