Huperzine A in rat plasma and CSF following intranasal administration

This paper presents to investigate the levels of Huperzine A in plasma and CSF of rats after three different kinds of administrations and to find out whether intranasal administration is the best route to transfer the drug into the CNS. The drugs of two doses (167 and 500 microg/kg) were administered to male Sprague-Dawley rats intravenously, intranasally and intragastricly, respectively. Series plasma and cerebrospinal fluid (CSF) samples were collected from femoral artery and cisterna magna for 6h. The drug concentrations were determined by HPLC-fluorescence method. The AUC(plasma) and the AUC(CSF) of intranasal administration were 90.3% and 127.7% in low dose group (167 microg/kg) and 91.3% and 69.4% in high dose group (500 microg/kg) compared with intravenous administration. The AUC(plasma) and the AUC(CSF) of intragastric administration were 98.9% and 52.1% in high dose group (500 microg/kg) compared with intravenous administration.