title: Nicotine ameliorates impairment of working memory in methamphetamine-treated rats.
abstract: Nicotine is hypothesized to have therapeutic effects on attentional and cognitive abnormalities in psychosis. In this study, we investigated the effect of nicotine on impaired spatial working memory in repeated methamphetamine (METH)-treated rats. Rats were administered METH (4 mg/kg, s.c.) once a day for 7 days, and their working memory was assessed with a delayed spatial win-shift task in a radial arm maze. The task consisted of two phases, a training phase and a test phase, separated by a delay. Control animals showed impaired performance in the test phase when the delay time was increased to 120 min or longer, while METH-treated rats showed impaired performance with a shorter delay time of 90 min. Memory impairment in METH-treated rats persisted for at least 14 days after drug withdrawal. METH-induced impairment of working memory was reversed by nicotine (0.3mg/kg, p.o., for 7 days), but the effect was diminished 7 days after the withdrawal. In control rats, nicotine decreased the number of working memory errors in the test with delay time of 120 min when administered before the training phase. Neither post-training nor pre-test administration of nicotine had any effect on working memory. These findings suggest that nicotine may have some protective effect against the impairment of working memory.
authors.affiliation: Futuristic Environmental Simulation Center, Research Institute of Environmental Medicine, Nagoya University, Nagoya 464-8601, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Mizoguchi
authors.forename: Daisuke
authors.initials: D
authors.lastname: Ibi
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Takase
authors.forename: Taku
authors.initials: T
authors.lastname: Nagai
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kamei
authors.forename: Erika
authors.initials: E
authors.lastname: Toth
authors.forename: Jun
authors.initials: J
authors.lastname: Sato
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Takuma
authors.forename: Kiyofumi
authors.initials: K
authors.lastname: Yamada
mesh_terms: D000818:Animals; D001288:Attention / Q000187:drug effects; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005508:Food Deprivation / Q000502:physiology; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008569:Memory Disorders / Q000139:chemically induced* / Q000188:drug therapy*; D008570:Memory, Short-Term / Q000187:drug effects*; D008694:Methamphetamine / Q000009:adverse effects*; D009538:Nicotine / Q000627:therapeutic use*; D018722:Nicotinic Agonists / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D013037:Spatial Behavior / Q000187:drug effects; D013566:Sympathomimetics / Q000009:adverse effects*; D013997:Time Factors
chemical_list: D018722:Nicotinic Agonists; D013566:Sympathomimetics; D008694:Methamphetamine; D009538:Nicotine