Pharmacokinetics and tissue distribution of coptisine in rats after oral administration by liquid chromatography-mass spectrometry.

Coptisine, one of the main components isolated from Coptidis rhizoma, has been reported to have many beneficial pharmacological effects including anti-inflammatory, anti-hypercholesterolemia, neuroprotective and cardioprotective properties. However, to date the information related to the in vivo pharmacokinetics (PK) of coptisine is very limited. The purposes of our study are to establish a fast and sensitive quantification method of coptisine using liquid chromatography-mass spectrometry (LC-MS) and evaluate the PK profile of coptisine in rats. The calibration curve for coptisine was linear from 0.78 to 50 ng/mL. After single-dose oral administration of coptisine, the mean peak plasma concentration values for groups treated with 30, 75 and 150 mg/kg doses ranged from 44.15 to 66.89 ng/mL, and the mean area under the concentration-time curve values ranged from 63.24 to 87.97 mg/L h. The absolute bioavailability was calculated to range from 1.87 to 0.52%. Coptisine remained in all analyzed samples at low concentrations after oral administration of 30 mg/kg.