title: Memory impairment induced by sodium fluoride is associated with changes in brain monoamine levels.
abstract: Previous studies suggest that sodium fluoride (NaF) can impair performance in some memory tasks, such as open-field habituation and two-way active avoidance. In the present study, we evaluated the effect of NaF intake (100 ppm in drinking water for 30 days) and its short-term (15 days) withdrawal on open-field habituation and brain monoamine level. Adult male rats were allocated to three groups: tap water (NaF 1.54 ppm) for 45 days (control group); 15 days of tap water followed by NaF for 30 days; and NaF for 30 days followed by 15 days of tap water. The results showed that NaF impairs open-field habituation and increases noradrenaline (NA) and serotonin (5-HT) in the striatum, hippocampus and neocortex. Dopamine (DA) increase was restricted to the striatum. Short-term NaF withdrawal did not reverse these NaF-induced changes, and both NaF treatments led to a mild fluorosis in rat incisors. No treatment effect was seen in body weight or fluid/water consumption. These results indicate that sodium fluoride induces memory impairment that outlasts short-term NaF withdrawal (2 weeks) and may be associated with NA and 5-HT increases in discrete brain regions.
authors: Laboratório de Fisiologia e Farmacologia do Sistema Nervoso Central, Departamento de Farmacologia, Setor de Ciências Biológicas, Universidade Federal do Paraná, Centro Politécnico, P.O. Box 19031, Curitiba, PR 81540-990, Brazil.
authors: Marcela
authors: M
authors: Pereira
authors: Patrícia A
authors: PA
authors: Dombrowski
authors: Estela M
authors: EM
authors: Losso
authors: Lea R
authors: LR
authors: Chioca
authors: Cláudio
authors: C
authors: Da Cunha
authors: Roberto
authors: R
authors: Andreatini
mesh_terms: D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D008297:Male; D008569:Memory Disorders / Q000139:chemically induced / Q000378:metabolism*; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D009638:Norepinephrine / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000378:metabolism*; D012969:Sodium Fluoride / Q000633:toxicity*
chemical_list: D015306:Biogenic Monoamines; D012701:Serotonin; D012969:Sodium Fluoride; D004298:Dopamine; D009638:Norepinephrine