Comparative study on pharmacokinetics of tetramethylpyrazine,ferulic acid and their compatibility

Objective: To study the pharmacokinetics of tetramethylpyrazine(TMP),ferulic acid and their compatibility.Method: Twenty-four Sprague-Dawley rats were randomly divided into 3 groups: TMP 20 mg·kg-1,ferulic acid 20 mg·kg-1 and TMP 20 mg·kg-1 + ferulic acid 20 mg·kg-1.All the rats were given intragastric administration then blood samples were obtained from fossa orbitalis at several time points.All the plasmas concentrations were analyzed by HPLC method and the data were treated by DAS 2.0 program.Result: The main pharmacokinetics parameters of TMP 20 mg·kg-1 group,ferulic acid 20 mg·kg-1and TMP 20 mg·kg-1+ ferulic acid 20 mg·kg-1were as follows: tmax 0.5 h,t1/2 0.856 h,MRT 1.321 h,AUC 5.112 μg·h-1·L-1,Cmax 2.834 μg·L-1;tmax 0.083 h,t1/2 1.024 h,MRT 1.324 h,AUC 1.581 μg·h-1·L-1,Cmax 1.492 μg·L-1;tmax 0.583 h,t1/2 37.901 h,MRT 3.798 h,AUC 4.097 μg·h-1·L-1,Cmax 1.571 μg·L-1;tmax 0.6 h,t1/2 7.860 h,MRT 2.894 h,AUC 1.984 μg·h-1·L-1,Cmax 1.03 μg·L-1,respectively.Conclusion: The experiments suggested that the compatibility of TMP and ferulic acid had interaction in pharmacokinetics;all the t1/2 and MRT were prolonged and had the effect of lente liberates.