title: Orexin A enhances locomotor activity and induces anxiogenic-like action in the goldfish, Carassius auratus.
abstract: Orexin acts as an orexigenic factor for the regulation of appetite and rhythmicity in rodents. In goldfish, intracerebroventricular (ICV) administration of orexin A has been shown to affect not only food intake, but also locomotor activity. However, as there is still no information regarding the effect of orexin A on emotional behavior in goldfish, we investigated the effect of orexin A on psychomotor activity in this species. Intracerebroventricular administration of synthetic orexin A at 2 and 4pmol/g body weight (BW) enhanced locomotor activity, and this enhancement by orexin A at 4pmol/g BW was attenuated by treatment with the orexin receptor 1 antagonist, SB334867, at 10pmol/g BW. Since intact goldfish prefer a black to a white background area, or the lower to the upper area of a tank, we used two types of preference tests (black/white and upper/lower tests) for measuring anxiety-like behavior in goldfish. Intracerebroventricular administration of orexin A at 4pmol/g BW shortened the time spent in the white background area, and increased the time taken to move from the lower to the upper area. This action of orexin A mimicked that of the central-type benzodiazepine receptor inverse agonist, FG-7142 (an anxiogenic agent), at 4pmol/g BW. The anxiogenic-like effect of orexin A was abolished by treatment with SB334867 at 10pmol/g BW. These results indicate that orexin A potently affects psychomotor activity in goldfish.
authors.affiliation: Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190-Gofuku, Toyama 930-8555, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Nakamachi
authors.affiliation: Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190-Gofuku, Toyama 930-8555, Japan.
authors.forename: Haruki
authors.initials: H
authors.lastname: Shibata
authors.affiliation: Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190-Gofuku, Toyama 930-8555, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sakashita
authors.affiliation: Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190-Gofuku, Toyama 930-8555, Japan.
authors.forename: Naoto
authors.initials: N
authors.lastname: Iinuma
authors.affiliation: Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190-Gofuku, Toyama 930-8555, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Wada
authors.affiliation: Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190-Gofuku, Toyama 930-8555, Japan.
authors.forename: Norifumi
authors.initials: N
authors.lastname: Konno
authors.affiliation: Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190-Gofuku, Toyama 930-8555, Japan; Laboratory of Regulatory Biology, Graduate School of Innovative Life Science, University of Toyama, 3190-Gofuku, Toyama 930-8555, Japan. Electronic address: kmatsuda@sci.u-toyama.ac.jp.
authors.forename: Kouhei
authors.initials: K
authors.lastname: Matsuda
mesh_terms: D000818:Animals; D001007:Anxiety / Q000139:chemically induced* / Q000523:psychology*; D001583:Benzoxazoles / Q000494:pharmacology; D002243:Carbolines / Q000494:pharmacology; D003975:Diazepam / Q000494:pharmacology; D004644:Emotions / Q000187:drug effects; D006054:Goldfish / Q000502:physiology*; D006993:Hypnotics and Sedatives / Q000494:pharmacology; D007276:Injections, Intraventricular; D047908:Intracellular Signaling Peptides and Proteins / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects*; D009287:Naphthyridines; D009479:Neuropeptides / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000068797:Orexins; D014508:Urea / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: C420062:1-(2-methylbenzoxazol-6-yl)-3-(1,5)naphthyridin-4-yl urea; D001583:Benzoxazoles; D002243:Carbolines; D006993:Hypnotics and Sedatives; D047908:Intracellular Signaling Peptides and Proteins; D009287:Naphthyridines; D009479:Neuropeptides; D000068797:Orexins; C035874:FG 7142; D014508:Urea; D003975:Diazepam
keywords: Anxiogenic-like action; Goldfish; ICV administration; Locomotor activity; Orexin A; Psychomotor activity