title: The influence of orexins on ethanol-induced behavioral sensitization in male mice.
abstract: Recent evidence indicates the involvement of orexin in reward circuitry and drug addiction. In the present study we evaluated the role of orexin in ethanol-induced behavioral sensitization. In the first experiment, Swiss male mice received seven administrations of saline or ethanol (2.2g/kg, i.p., chronic), every other day. On the last day of treatment, half of saline-treated mice received a saline injection (saline) whereas the other half received 2.2g/kg of ethanol (i.p., acute). Behavioral sensitization was assessed by locomotor activity tests and after the last one, immunoreactivity for orexin and Fos (ORX+Fos-ir) was assessed in the lateral hypothalamic area. Chronic ethanol treatment produced behavioral sensitization and a trend for greater ORX+Fos-ir. In the second experiment, mice were treated as in Experiment 1 and type 1 orexin receptor antagonist, SB334867 (20mg/kg), was administered before the ethanol challenge successfully blocking the expression of sensitization in mice chronically treated with EtOH. These results indicate that orexin plays a role in ethanol-induced behavioral sensitization.
authors.affiliation: Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, Brazil.
authors.forename: Giovana Camila
authors.initials: GC
authors.lastname: Macedo
authors.forename: Suzi Emiko
authors.initials: SE
authors.lastname: Kawakami
authors.forename: Thiago
authors.initials: T
authors.lastname: Vignoli
authors.forename: Rita
authors.initials: R
authors.lastname: Sinigaglia-Coimbra
authors.forename: Deborah
authors.initials: D
authors.lastname: Suchecki
mesh_terms: D000818:Animals; D000431:Ethanol / Q000494:pharmacology*; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008297:Male; D051379:Mice; D009043:Motor Activity / Q000187:drug effects*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D009479:Neuropeptides / Q000378:metabolism*; D000068797:Orexins; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D000068797:Orexins; D016760:Proto-Oncogene Proteins c-fos; D000431:Ethanol
keywords: Behavioral sensitization; Ethanol; Fos; Immunohistochemistry; Orexin type 1 receptor