RÉSUMÉ
Objective: To investigate the inhibition of rutaecarpine, a main component in Evodiae Fructus, on the hepatic metabolism of five Coptis alkaloids, and to provide the basis for further study of compatibility mechanism between Coptidis Rhizoma and Evodiae Fructus. Methods: Using rat liver microsome incubation method, the inhibition of rutaecarpine on hepatic metabolism of five Coptis alkaloids in vitro was investigated. Results: Rutaecarpine could inhibit the in vitro hepatic metabolisms of coptisine, epiberberine, berberine, palmatine, and jatrorrhizine. The half inhibitory concentration (IC50) was all greater than 50 μmol/L which showed rutaecarpine had a weak inhibition on Coptis alkaloids. The differences of inhibition constant (Ki) were statistically significant (P jatrorrhizine > palmatine > epiberberine > coptisine. Conclusion: The results could provide the basis to learn the major role on the links that Evodiae Fructus acted on Coptis alkaloids and reveal the compatibility mechanism between Coptidis Rhizoma and Evodiae Fructus.
RÉSUMÉ
Objective: To explore the in vitro hepatic metabolic selectivity of five kinds of isoquinoline alkaloids (with the similar structures) from Coptis chinensis in rats. Methods: Using the method of rat in vitro liver microsomes incubation model, the metabolic kinetics parameters Km, Vmax, and CLint for berberine, palmatine, coptisine, epiberberine, and jateorhizine were calculated by observing the influence of incubation time, protein concentration of liver microsomes, and substrate concentration on metabolic characteristics in liver. Results: The difference of in vitro hepatic metabolic kinetics parameters Km and CLint among five kinds of alkaloids from C. chinensis is statistically significant (P < 0.05). Conclusion: There is a significant selectivity in in vitro hepatic metabolism of five kinds of isoquinoline alkaloids from C. chinensis in rats.