Pharmacokinetics of a Chinese traditional medicine, danshensu (3,4-dihydroxyphenyllactic acid), in rabbits using high-performance liquid chromatography.

An injectable solution of Danshen was prepared and its in vivo disposition was examined in rabbits. The presence of Danshensu, one of the active components of Danshen, in the obtained solution was confirmed by a simple high-performance liquid chromatographic (HPLC) method. The pharmacokinetics of Danshensu in rabbits was evaluated by the HPLC method for plasma Danshensu. The calibration curve for Danshensu was linear (r = 0.998) over the concentration range of 0.25-40.0 micrograms/ml. The intra-assay coefficients of variation (CVs) were 3.8, 3.1, and 3.1% at 1, 10, and 50 micrograms/ml, respectively, and the inter-assay CVs were 5.3, 5.3, and 2.9% at 1, 10, and 50 micrograms/ml, respectively. The analytical recovery of Danshensu in plasma averaged 95.2%. From the plasma concentration profile of Danshensu after its intravenous administration, the t1/2, mean residence time (MRT), Vdss, and Cltot were determined as 32 min, 48 min, 149 ml/kg, and 3.13 ml/min/kg, respectively.