Abstract:Objective: To develop a HPLC method for determination of the concentration of Danshensu in rat plasma and undertake comparative pharmacokinetic study of sodium danshensu and Salvia miltiorrhiza injection in rat as well as to assess the effect of other components of Salvia miltiorrhiza injection on the pharmacokinetics of Danshensu. Method: Rats received an iv infusion of sodium Danshensu or S. miltiorrhiza injection(equal to Danshensu 30 mg·kg-1). Blood samples were collected from carotid artery. Plasma concentration of Danshensu extracted with perchloric acid was measured. The pharmacokinetic parameters were calculated with DAS2.0 software. Result: A good linear relationship of Danshensu was obtained from the range of 0.5 to 80.0 mg·L-1, and the lowest limit of determination was 0. 2 mg·L-1. The plasma concentration time curves of Danshensu were best fitted with two-compartment models for Danshensu itself and for Salvia miltiorrhiza injection as well. The pharmacokinetic parameters such as t1/2α, AUC, CL had significant differences. Conclusion: The concomitant components in Salvia miltiorrhiza injection influence the pharmacokinetic properties of Danshensu and speed up its disposition and elimination.