Background: The synergistic effect of dihydromyricetin (DHM) and fluconazole (FLC) can improve the killing effect of FLC-resistant Candida albicans in vitro and in vivo. However, it is not clear whether DHM affects the pharmacokinetic characteristics of FLC.
Methods: In this study, 12 Sprague–Dawley (SD) rats were randomly divided into two groups as follows: (1) an FLC group in which rats were administered FLC only (42 mg/kg orally); (2) an FLC with the combined administration of DHM group, in which rats received an equivalent FLC dose immediately following the administration of DHM (100 mg/kg). Blood samples were collected from the ocular choroid vein of rats and converted into plasma. The concentrations of FLC in the rat plasma were then determined by high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS), and the related pharmacokinetic parameters were analysed. The initial mobile phase included 0.1% acetonitrile and water with gradient elution. Multiple reaction monitoring modes of m/z 307.2→ 220.1 for FLC, and m/z 237.1→ 194.2 for carbamazepine, were utilised to conduct quantitative analysis.
Results: The calibration curve of FLC in rat plasma demonstrated good linearity in the range of 0.1– 30 μg/mL (r > 0.99), and the lower limit of quantification was 0.1 μg/mL. Moreover, the intra- and inter-day precision relative standard deviation of FLC was less than 9.09% and 6.51%, respectively. There were no significant differences in the pharmacokinetic parameters between the two groups.
Conclusion: The results showed that DHM administration did not significantly alter FLC pharmacokinetics in SD rat plasma.
Keywords: HPLC-MS/MS, dihydromyricetin, fluconazole, pharmacokinetic