Pharmacokinetics and Tissue Distribution of Orientin from Trollius chinensis in Rabbits

Objective To study the pharmacokinetics(PK) and tissue distribution of orientin in rabbits. Methods The high-performance liquid chromatography method was developed and validated for the determination of orientin in rabbit plasma and tissues. The PK characteristics of orientin in rabbits were compared by three kinds of administration, iv, im, and ip injection, using 3P97 pharmacokinetic software to examine the PK parameters. Results The elimination half-life(t1/2β) of three kinds of administration was higher than the distribution half-life(t1/2α). The PK of orientin eliminating in rabbit fitted the two compartment model. Orientin was mainly eliminated in rabbit. The distribution of orientin in tissue after iv injection was investigated, and the order of orientin AUC in each group was kidney > liver > lung > spleen > heart > brain. Conclusion Orientin is distributed extensively in tissues such as kidney, liver, and lung. It is difficult for orientin to cross the blood brain barrier.