title: Avoidance behavior and brain monoamines in fish.
abstract: The crucian carp performs a typical avoidance behavior when exposed to olfactory cues from injured skin of conspecifics. They swim rapidly to the bottom and hide in available material. This work examines the effects of skin extract exposure and availability of hiding material on this behavior, and concomitant changes in brain monoaminergic activity in crucian carp. Individual fish were exposed to skin extract in aquaria with or without hiding material. Exposure to skin extract resulted in the expected avoidance behavior consisting of rapid movement towards the bottom of the aquarium. This lasted for 1-2 min. Activity then decreased below the level observed before exposure, suggesting a "freezing" type of avoidance behavior. This behavior was independent of availability of hiding material. Brain dopaminergic activity increased in telencephalon and decreased in the brain stem following skin extract exposure, again independent of availability of hiding material. However, fish kept in aquaria without hiding material showed an elevation of serotonergic activity in the brain stem and the optic tectum compared to fish with available hiding material. Absence of hiding material increased serotonergic activity also without exposure to skin extract. In aquaria with hiding material, the fish stirred up a cloud of fine sediments and showed a more pronounced decrease in locomotor activity in agreement with this being a more efficient freezing or immobile avoidance behavior. These results show that basic components of avoidance behavior and related brain changes are present in the fish brain, in accordance with the common phylogenetic roots of avoidance behavior in all vertebrates.
authors.affiliation: Department of Molecular Biosciences, University of Oslo, PO Box 1041 Blindern, 0316 Oslo, Norway.
authors.forename: Erik
authors.initials: E
authors.lastname: Höglund
authors.forename: Finn-Arne
authors.initials: FA
authors.lastname: Weltzien
authors.forename: Joachim
authors.initials: J
authors.lastname: Schjolden
authors.forename: Svante
authors.initials: S
authors.lastname: Winberg
authors.forename: Holger
authors.initials: H
authors.lastname: Ursin
authors.forename: Kjell B
authors.initials: KB
authors.lastname: Døving
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001362:Avoidance Learning / Q000502:physiology*; D001522:Behavior, Animal; D015306:Biogenic Monoamines / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D001923:Brain Chemistry / Q000502:physiology; D002347:Carps; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004924:Escape Reaction / Q000502:physiology*; D009043:Motor Activity / Q000502:physiology; D009812:Odorants; D009833:Olfactory Pathways / Q000187:drug effects; D012867:Skin / Q000737:chemistry
chemical_list: D015306:Biogenic Monoamines