Study on Pharmacokinetics of Gastrodin after Tianma Extract in Rats

Objective: To study on the pharmacokinetics of gastrodin after Tianma extract(equivalent to gastrodin 50,100,200mg·kg-1) in rats.Methods: HPLC was used to determine gastrodin plasma concentration at different times after the rats were orally administered three dosage levels of Tianma extract.The mean plasma concentration-time curves of different medication administration teams were processed by WinNonlin 5.2.1 pharmacokinetic software.The pharmacokinetic parameters of different medication administration teams were analyzed by SPSS statistics 17.0 software.Results: T1/2,CL/F,MRT0-10h was no significant difference,and AUC0-10h was linear increase between low and middle dosage group.Meanwhile,T1/2 was significantly decreased and MRT0-10h was significantly prolonged between high dosage group and middle dosage group.Conclusion: The results indicated that the in vivo kinetic process of gastrodin were fitted to first-order linear absorption un-compartment model at dosage range of 50-100mg·kg-1,and zero-order nonlinaer absorption un-compartment model at the dosage more than 200mg·kg-1.