Intracerebroventricular injection of neosurugatoxin induces a prolonged blockade of brain nicotinic acetylcholine receptors.
The intracerebroventricular injection of neosurugatoxin (2 x 3.2 micrograms) significantly reduced the specific binding of [3H]nicotine but not of [3H]cismethyldioxolane in the cerebral cortex, hippocampus and thalamus of rats 3 days after the toxin injection. Scatchard analysis of [3H]nicotine binding in the rat cerebral cortex revealed that neosurugatoxin can selectively decrease the maximal binding sites (Bmax) for [3H]nicotine by approximately 38%. A significant decrease in the Bmax value for [3H]nicotine was also observed in this brain region 7 days after the neosurugatoxin injection. Thus, the intracerebroventricular injection of neosurugatoxin can induce a prolonged blockade of brain nicotinic acetylcholine receptors.
Yamada
S
S
Department of Pharmacology, Shizuoka College of Pharmaceutical Sciences, Japan.
Ushijima
H
H
Nakayama
K
K
Hayashi
E
E
Tsuji
K
K
Kosuge
T
T
D000818:Animals; D001665:Binding Sites; D001921:Brain / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism; D007031:Hypothalamus / Q000378:metabolism; D007276:Injections, Intraventricular; D008297:Male; D008978:Mollusk Venoms / Q000008:administration & dosage*; D009538:Nicotine / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011950:Receptors, Cholinergic / Q000187:drug effects / Q000378:metabolism*; D011978:Receptors, Nicotinic / Q000187:drug effects / Q000378:metabolism
D008978:Mollusk Venoms; D011950:Receptors, Cholinergic; D011978:Receptors, Nicotinic; D009538:Nicotine; C036793:neosurugatoxin