Format

Send to

Choose Destination
See comment in PubMed Commons below
Acta Pharmacol Sin. 2006 Sep;27(9):1127-36.

Comparative studies of huperzine A, donepezil, and rivastigmine on brain acetylcholine, dopamine, norepinephrine, and 5-hydroxytryptamine levels in freely-moving rats.

Author information

1
State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Instituties for Biological Sciences, Graduate School of the Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 201203, China.

Abstract

AIM:

To assess the effects of cholinesterase inhibitors huperzine A, donepezil and rivastigmine on cerebral neurotransmitters in the cortex and hippocampus in freely-moving rats.

METHODS:

Double-probe cerebral microdialysis and HPLC with electrochemical detection were used to detect neurotransmitters.

RESULTS:

Our results showed that huperzine A (0.25, 0.5, and 0.75 micromol/kg, po) dose-dependently elevated extracellular acetylcholine (ACh) levels in the medial prefrontal cortex (mPFC) and hippocampus. Oral administration of donepezil (5.4 micromol/kg) or rivastigmine (1 micromol/kg) also elicited significant increases in ACh in the mPFC and hippocampus. The time course of cortical acetylcholinesterase (AChE) inhibition with the 3 inhibitors mirrored the increases of ACh at the same dose. The marked elevation of ACh after oral administration of huperzine A (0.5 micromol/kg) and donepezil (5.4 micromol/kg) was associated with a significantly increased release of dopamine (DA) in the mPFC or hippocampus. None of the 3 inhibitors affected norepinephrine (NE) and 5-hydroxytryptamine (5-HT) levels in the mPFC and hippocampus. The effects of huperzine A and rivastigmine did not depend on the route of administration, but donepezil was less efficacious by the oral route than by ip injection. The ability of huperzine A to increase ACh levels was unchanged when tests were performed after multiple oral administration of the drug at 0.5 micromol/kg, once per day for 30 d.

CONCLUSION:

The present findings showed that, in molar terms, huperzine A had similar potency on increasing mPFC ACh and DA levels as compared to the 11- and 2-fold dosages of donepezil and rivastigmine, respectively, and had longer lasting effects after oral dosing.

[Indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Nature Publishing Group
    Loading ...
    Support Center