title: Fluoxetine and WAY 100,635 dissociate increases in scototaxis and analgesia induced by conspecific alarm substance in zebrafish (Danio rerio Hamilton 1822).
abstract: Alarm reactions to a substance secreted by the damaged skin of conspecifics and closely-related species are increasingly being recognized as fear-like responses in fish. The neurochemical underpinnings of these effects are so far unknown; however, given the role of the serotonergic system on defensive behavior, it is possible that the alarm reaction is mediated by this monoamine. Exposure to conspecific alarm substance (CAS) increased anxiety-like behavior in the light/dark test in zebrafish and decreased nocifensive behavior. These effects were accompanied by increases in blood glucose, hemoglobin, epinephrine and norepinephrine levels, as well as extracellular levels of serotonin in the brain. Pretreatment with fluoxetine blocked the anxiogenic effects of CAS on the light/dark test as well as all physiological parameters and the increase in extracellular brain 5-HT, but not the reduction in nocifensive behavior. Conversely, pretreatment with the 5-HT1AR antagonist WAY 100635 blocked the effects on nocifensive behavior, but not the effects on anxiety-like behavior nor on physiological parameters. These results point to an important and complex role of the serotonergic system in the mediation of fear-potentiated behavior in the light/dark test and in fear-induced analgesia in zebrafish.
authors.affiliation: Departamento de Morfologia e Ciências Fisiológicas, Universidade do Estado do Pará, Marabá, PA, Brazil; International Zebrafish Neuroscience Research Consortium, USA. Electronic address: caio.maximino@gmail.com.
authors.forename: Caio
authors.initials: C
authors.lastname: Maximino
authors.affiliation: Departamento de Morfologia e Ciências Fisiológicas, Universidade do Estado do Pará, Marabá, PA, Brazil; International Zebrafish Neuroscience Research Consortium, USA.
authors.forename: Monica Gomes
authors.initials: MG
authors.lastname: Lima
authors.affiliation: Programa de Educação Tutorial PET Medicina/Enfermagem, Instituto de Ciências da Saúde, Universidade Federal do Pará, Belém, PA, Brazil.
authors.forename: Carina Cardoso
authors.initials: CC
authors.lastname: Costa
authors.affiliation: Programa de Educação Tutorial PET Medicina/Enfermagem, Instituto de Ciências da Saúde, Universidade Federal do Pará, Belém, PA, Brazil; Laboratório de Biologia Celular e Molecular do Citoesqueleto, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil.
authors.forename: Iêda Maria Louzada
authors.initials: IM
authors.lastname: Guedes
authors.affiliation: International Zebrafish Neuroscience Research Consortium, USA; Laboratório de Neuroendocrinologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil.
authors.forename: Anderson Manoel
authors.initials: AM
authors.lastname: Herculano
mesh_terms: D000698:Analgesia; D000818:Animals; D005239:Fear; D005473:Fluoxetine / Q000494:pharmacology*; D010879:Piperazines / Q000494:pharmacology*; D011725:Pyridines / Q000494:pharmacology*; D012701:Serotonin / Q000502:physiology; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology*; D015027:Zebrafish / Q000502:physiology*
chemical_list: D005473:Fluoxetine; D010879:Piperazines; D011725:Pyridines; D012701:Serotonin; D017367:Selective Serotonin Reuptake Inhibitors; C090413:N-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridinyl)cyclohexanecarboxamide
keywords: Alarm substance; Fear; Nocifensive behavior; Scototaxis; Serotonin; Zebrafish