Pharmacokinetics and metabolites of scutellarin in normal and model rats

AimTo investigate the pharmacokinetics and metabolites of scutellarin in normal rats and rats with thrombosis model induced by carrageenan. MethodsScutellarin was assayed by reverse phase high performance liquid chromatography in various plasma samples after a single dose of 36 mg·kg^-1 iv to each rat, the pharmacokinetic parameters were estimated by 3P97 program. The metabolites of scutellarin in blood were chromatographed and identified by HPLC-PDA, LC/MS/MS. ResultsThe calibration curve was linear over the range from 0.625 to 80.0 μg·mL^-1 (r=0.999 5), the limit quantitation was 0.312 μg·mL^-1. The plasma scutellarin concentration-time curve was fitted to the open two-compartment model. In the plasma samples, the main metabolites were deduced as 4′,5-dihydroxyflavonon-7-O-β-D-glucuronopyranosyl ester (M1), scutellarin (M2), 7-methoxy-4′,5-dihydroxy-flavonon (M3) and 7-methoxy-4′,5,6-dihydroxy-flavonon (M4). ConclusionThe pharmacokinetic parameters of scutellarin were significantly different in normal and model rats. The metabolic pathways of scutellarin was proposed to be dehydroxylation and methylation.