title: Effects of alpha4beta2 and alpha7 nicotinic acetylcholine receptor antagonists on place aversion induced by naloxone in single-dose morphine-treated rats.
abstract: Acute dependence can be observed when naloxone is administered 24 h after even a single dose of morphine, and nicotine attenuates this naloxone-precipitated withdrawal syndrome. This acute dependence has been hypothesized to be associated with a dopaminergic mechanism. In the present study, the role of nicotinic acetylcholine receptor subtypes in the place aversion induced by naloxone in single-dose morphine-treated rats was investigated. Methyllycaconitine (1, 2 and 5 mg/kg), an alpha7 nicotinic acetylcholine receptor subtype inhibitor, significantly and dose dependently inhibited the attenuating effect of nicotine on naloxone-induced place aversion. In contrast, dihydroxy-beta-erithroidine (1, 2 and 5 mg/kg), an alpha4beta2 nicotinic acetylcholine receptor subtype inhibitor, did not have any effect on the attenuating effect of nicotine on naloxone-induced place aversion. These findings suggested that the alpha7 nicotinic acetylcholine receptor subtype is associated with the place aversion induced by naloxone in single-dose morphine-treated rats. Nicotinic acetylcholine receptor subtype inhibitors warrant further study as possible treatment for acute dependence.
authors.affiliation: Onomichi Municipal Hospital Hiroshima, 3-1170-177 Shintakayama, Onomichi, Hiroshima 722-8503, Japan.
authors.forename: Seiki
authors.initials: S
authors.lastname: Motoshima
authors.forename: Katsuya
authors.initials: K
authors.lastname: Suemaru
authors.forename: Youichi
authors.initials: Y
authors.lastname: Kawasaki
authors.forename: Chunyu
authors.initials: C
authors.lastname: Jin
authors.forename: Hiromu
authors.initials: H
authors.lastname: Kawasaki
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Gomita
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Araki
mesh_terms: D000157:Aconitine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D003216:Conditioning, Operant / Q000187:drug effects* / Q000502:physiology; D004079:Dihydro-beta-Erythroidine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D009270:Naloxone / Q000494:pharmacology*; D009292:Narcotic Antagonists / Q000494:pharmacology; D009294:Narcotics / Q000494:pharmacology; D009538:Nicotine / Q000494:pharmacology; D018722:Nicotinic Agonists / Q000494:pharmacology; D018733:Nicotinic Antagonists / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011978:Receptors, Nicotinic / Q000502:physiology; D064569:alpha7 Nicotinic Acetylcholine Receptor
chemical_list: C579165:Chrna7 protein, rat; D009292:Narcotic Antagonists; D009294:Narcotics; D018722:Nicotinic Agonists; D018733:Nicotinic Antagonists; D011978:Receptors, Nicotinic; D064569:alpha7 Nicotinic Acetylcholine Receptor; C403531:nicotinic receptor alpha4beta2; C054634:methyllycaconitine; D004079:Dihydro-beta-Erythroidine; D009270:Naloxone; D009538:Nicotine; D009020:Morphine; D000157:Aconitine