Abstract: Aim To study the pharmacokinetic characters of Dauricine in dogs.Methods Dauricine was applied in 5 dosages of two administration ways 5 dogs according to Latin Square plan. The drug plasma concentration was determined by RP-HPLC.Results Dauricine spread quickly from central compartment to spherical compartment after intravenous administration of 6 mg·kg^-1.The t_{1/2 (α)} was 6~12min, K₁₂>K₂₁.The mean t_{1/2 (β)} was (2.7±0.4) h,V_d was about 11.18 L·kg^-1.The C-T profile conformed to two compartment open model.The plasma Dau concentration-time curves showed a double-peak phenomenon in all dosages of all dogswhen dauricine was given by intragastric was.The t_peak(1)was (0.8±0.6)~(1.2±0.5)h, t_peak(2) was (5.2±3.2)~(6.5±1.9) h, C_max(2)< C_max(1). Dauricine was eliminated linearly in the do sages of 12.5 and 25 mg·kg^-1,there was no obvious difference of parameters t_1/2(el),CL,AUC/X₀ between them (P>0.05)and the AUC was increased in pro portion.The drug is eliminated non-linearly when the dosage is above 50 mg·kg_-1,the parameters t_1/2(el), CL,A UC/X₀ shows great difference (P<0.01)comparing with dosage 12.5 mg·kg_-1,AUC was increased out of pro portion.Conclusion The plasma drug co ncentration-time curve of Dau afterig administration in dogs shows a double-peak phenomenon.A saturated character in Dauricine’s elimination is observed when the dosage is over or equal to 50mg·kg^-1.

Key words: dauricine, pharmacokinetics, RP-HPLC