Pharmacokinetic Comparisons of Morroniside in Rats after Oral Administration of Pure Morroniside, Fructus Corni Extract and Liuwei Dihuang Pills

Liuwei Dihuang is a typical Traditional Chinese Medicine prescription with the effect of nourishing "Kidney-Yin". It has many chemical constituents, and morroniside was one of the main bioactive constituent. But whether other ingredients can influence the pharmacokinetics of morroniside has not been reported. The aim of this study was to compare the pharmacokinetics of morroniside in rats after oral administration of pure morroniside, Fructus Corni extract and Liuwei Dihuang pills and explore the influence of other herbal ingredients in Liuwei Dihuang Pills on the pharmacokinetics of morroniside. Eighteen Wistar rats were randomly divided into three groups and orally administrated with morroniside water solution, Fructus Corni extract and LW pills CMC-Na suspension at a dosage of 20 mg/kg, respectively. Venous blood samples were collected through jugular sinus before and 0.083, 0.167, 0.25, 0.5, 0.75, 1, 1.5, 2, 3, 4, 6, 8, 12, 24 h after administration. Plasma concentration of morroniside was determined using a simple and rapid LC-MS method. The parameters were calculated using Drug and Statistical Software-Version 2.1.1 and unpaired Student's t-test was used for the statistical comparison. A bimodal phenomenon was observed in the plasma profile after oral administration of LW pills. The results showed that among calculated parameters, AUC(0-t), AUC(0-infinity), MRT0-t, t(1/2), CL and V, there were significant differences between LW pills group and pure morroniside group ( P < 0.05). But there were no significant differences between Fructus Corni extract group and pure morroniside. Some ingredients of other herbal in LW prescription may influence the elimination and bioavailability of morroniside.