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 root to transfer the drug into the CNS. The drugs of two doses (167 and 500μg/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 AUCplasma and the AUCCSF of intranasal administration were 90.3% and 127.7% in low dose group (167μg/kg) and 91.3% and 69.4% in high dose group (500μg/kg) compared with intravenous administration. The AUCplasma and the AUCCSF of intragastric administration were 98.9% and 52.1% in high dose group (500μg/kg) compared with intravenous administration.