Pharmacokinetics of costunolide and dehydrocostuslactone after oral administration of Radix aucklandiae extract in normal and gastric ulcer rats.

Costunolide and dehydrocostuslactone are the main active ingredients of Radix Aucklandiae (RA). An accurate and sensitive LC-MS/MS method was established to simultaneously determine contents of costunolide and dehydrocostuslactone in plasma. There were significant differences in pharmacokinetic parameters (AUC0-t, Cmax,1, Cmax,2, Tmax,1, Vd, and CL) of costunolide and dehydrocostuslactone between RA group and costunolide group or dehydrocostuslactone group. The relative bioavailability of costunolide or dehydrocostuslactone of RA extract was improved. As compared to normal group, the Tmax,2 values of dehydrocostuslactone of RA in gastric ulcer group were prolonged, while the Cmax,1, Cmax,2, and AUC0-t values decreased.