Effects of isovanihuperzine A on cholinesterase and scopolamine-induced memory impairment.
OBJECTIVE
To study the effects of isovanihuperzine A (IVHA) on cholinesterase and scopolamine-induced memory deficit.


METHODS
AChE and BuChE activities were determined by the colorimetric method of Ellman. The Ki value was determined by the plotting method of Lineweaver and Burk. In a behavioral test, rats were trained to perform a radial arm maze task using a partially baited procedure.


RESULTS
The anti-AChE activity of IVHA was comparable to huperzine A (Hup-A), and was more potent than those of physostigmine and galanthamine with an IC50 value of 0.11 mumol.L-1. IVHA was a mixed competitive type with a Ki value of 32 nmol.L-1. It bound to AChE in a reversible manner. IVHA at a dose of 0.2 mg.kg-1 ip significantly reversed scopolamine-induced working memory and reference memory impairments in radial arm maze.


CONCLUSIONS
IVHA is a new potential reversible AChE inhibitor and merits further study as a cognitive enhancer.
Xiong
Z Q
ZQ
Department of Pharmacology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences.
Tang
X C
XC
Lin
J L
JL
Zhu
D Y
DY
D000110:Acetylcholinesterase / Q000378:metabolism*; D000818:Animals; D002800:Cholinesterase Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D004910:Erythrocyte Membrane / Q000201:enzymology; D008297:Male; D008569:Memory Disorders / Q000139:chemically induced / Q000188:drug therapy*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012601:Scopolamine; D012717:Sesquiterpenes / Q000494:pharmacology* / Q000627:therapeutic use
D002800:Cholinesterase Inhibitors; D012717:Sesquiterpenes; C093837:isovanihuperzine A; D012601:Scopolamine; D000110:Acetylcholinesterase