title: Possible role of serotoninergic system in the neurobehavioral impairment induced by acute methylmercury exposure in zebrafish (Danio rerio).
abstract: Adult zebrafish were treated acutely with methylmercury (1.0 or 5.0 μg g(-1), i.p.) and, 24h after treatment, were tested in two behavioral models of anxiety, the novel tank and the light/dark preference tests. At the smaller dose, methylmercury produced a marked anxiogenic profile in both tests, while the greater dose produced hyperlocomotion in the novel tank test. These effects were accompanied by a decrease in extracellular levels of serotonin, and an increase in extracellular levels of tryptamine-4,5-dione, a partially oxidized metabolite of serotonin. A marked increase in the formation of malondialdehyde, a marker of oxidative stress, accompanied these parameters. It is suggested that methylmercury-induced oxidative stress produced mitochondrial dysfunction and originated tryptamine-4,5-dione, which could have further inhibited tryptophan hydroxylase. These results underscore the importance of assessing acute, low-level neurobehavioral effects of methylmercury.
authors.affiliation: Laboratório de Neuroendocrinologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Brazil. caio@ufpa.br
authors.forename: Caio
authors.initials: C
authors.lastname: Maximino
authors.forename: Juliana
authors.initials: J
authors.lastname: Araujo
authors.forename: Luana Ketlen Reis
authors.initials: LK
authors.lastname: Leão
authors.forename: Alan Barroso Araújo
authors.initials: AB
authors.lastname: Grisolia
authors.forename: Karen Renata Matos
authors.initials: KR
authors.lastname: Oliveira
authors.forename: Monica Gomes
authors.initials: MG
authors.lastname: Lima
authors.forename: Evander de Jesus Oliveira
authors.initials: Ede J
authors.lastname: Batista
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Crespo-López
authors.forename: Amauri
authors.initials: A
authors.lastname: Gouveia
authors.forename: Anderson Manoel
authors.initials: AM
authors.lastname: Herculano
mesh_terms: D000818:Animals; D001007:Anxiety / Q000139:chemically induced / Q000378:metabolism / Q000503:physiopathology; D001522:Behavior, Animal / Q000187:drug effects*; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005260:Female; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D020262:Mercury Poisoning, Nervous System / Q000503:physiopathology*; D008767:Methylmercury Compounds / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects; D012701:Serotonin / Q000378:metabolism*; D013347:Subcellular Fractions / Q000378:metabolism; D015027:Zebrafish / Q000378:metabolism* / Q000502:physiology
chemical_list: D008767:Methylmercury Compounds; D012701:Serotonin; C004925:methylmercuric chloride