Effects of tetramethylpyrazine and ferulic acid on pharmacokinetics of tetrahydropalmatine in rats / 中草药

ABSTRACT

Objective: To investigate the effects of tetramethylpyrazine (TMP) and ferulic acid (FA) on pharmacokinetics of tetrahydropalmatine (THP) in rats. Methods: Thirty-two Sprague-Dawley rats were randomly divided into four groups such as THP 20 mg∙kg-1, THP 20 mg∙kg-1 + FA 50 mg∙kg-1, THP 20 mg∙kg-1 + TMP 30 mg∙kg-1, and THP 20 mg∙kg-1 + FA50 mg∙kg-1 + TMP 30 mg∙kg-1 groups. All the rats were ig administered and then blood samples were obtained from fossa orbitalis at several time points. All the plasma concentration was analyzed by RP-HPLC method and the data were treated by DAS 2.0 program. Results: Compared with THP alone, THP combined with TMP or FA could increase the AUC0~t, tmax, and Cmax, and prolong the t1/2 and MRT0~t (P < 0.05). Compared with THP alone, THP combined with TMP and FA could increase the AUC0~t, MRT0~t, t1/2, and tmax, but had no influence on the Cmax. Conclusion: FA and TMP can prolong the action time of THP in rats, and increase of THP absorption in rats in vivo.