Pharmacokinetic study of salvianolic acid A in beagle dog after oral administration by a liquid chromatography-mass spectrometry method: a study on bioavailability and dose proportionality.

ETHNOPHARMACOLOGICAL RELEVANCE

Salvianolic acid A (SAA) is one of the main water-soluble components isolated from Salvia miltiorrhiza Bunge. Pharmacological researches revealed that it had various curative activities after oral and intravenous administration, including beneficial effects on diabetes and its complications, cardioprotective effect, anti-platelet aggregation, and so on. However, there is no report regarding the pharmacokinetics of SAA in beagle dogs after oral administration up to now.

AIM OF THE STUDY

To study the pharmacokinetics of different doses of SAA in beagle dogs and figure out the absolute bioavailability and dose proportionality of SAA after oral administration.

MATERIALS AND METHODS

Male and female beagle dogs were orally administered SAA 5, 10 and 20mg/kg randomly. The plasma drug concentration was detected by a rapid, sensitive and reproducible liquid chromatography-mass spectrometry (LC-MS) method. The pharmacokinetic parameters were calculated from plasma concentration-time data using the DAS pharmacokinetic software Data Analysis System Version 3.0 program.

RESULTS

After single-dose oral administration of SAA, the mean peak plasma concentration (Cmax) values for groups treated with 5, 10 and 20 mg/kg doses ranged from 14.38 to 38.18 µg/L, and the mean area under the concentration-time curve (AUC(0-t)) values ranged from 38.77 to 130.33 (µg/L·h). SAA showed lack of dose proportionality over the dose range 5-20mg/kg, based on the power model. However, the increase in systemic exposure with dose appeared linear. The absolute bioavailability was calculated to range from 1.47% to 1.84%.

CONCLUSION

The pharmacokinetic properties of SAA in beagle dogs after oral administration were characterized as rapid oral absorption, quick clearance, and poor absolute bioavailability. Systemic exposure exhibited lack of dose proportionality over the dose range 5-20mg/kg. Furthermore, a readily preparative LC-MS method was demonstrated in this study for the research of traditional Chinese medicine.