title: Neurogenesis-dependent and -independent effects of fluoxetine in an animal model of anxiety/depression.
abstract: Understanding the physiopathology of affective disorders and their treatment relies on the availability of experimental models that accurately mimic aspects of the disease. Here we describe a mouse model of an anxiety/depressive-like state induced by chronic corticosterone treatment. Furthermore, chronic antidepressant treatment reversed the behavioral dysfunctions and the inhibition of hippocampal neurogenesis induced by corticosterone treatment. In corticosterone-treated mice where hippocampal neurogenesis is abolished by X-irradiation, the efficacy of fluoxetine is blocked in some, but not all, behavioral paradigms, suggesting both neurogenesis-dependent and -independent mechanisms of antidepressant action. Finally, we identified a number of candidate genes, the expression of which is decreased by chronic corticosterone and normalized by chronic fluoxetine treatment selectively in the hypothalamus. Importantly, mice deficient in one of these genes, beta-arrestin 2, displayed a reduced response to fluoxetine in multiple tasks, suggesting that beta-arrestin signaling is necessary for the antidepressant effects of fluoxetine.
authors.affiliation: Université Paris-Sud EA 3544, Faculté de Pharmacie, Châtenay-Malabry Cedex F-92296, France. denis.david@u-psud.fr
authors.forename: Denis J
authors.initials: DJ
authors.lastname: David
authors.forename: Benjamin Adam
authors.initials: BA
authors.lastname: Samuels
authors.forename: Quentin
authors.initials: Q
authors.lastname: Rainer
authors.forename: Jing-Wen
authors.initials: JW
authors.lastname: Wang
authors.forename: Douglas
authors.initials: D
authors.lastname: Marsteller
authors.forename: Indira
authors.initials: I
authors.lastname: Mendez
authors.forename: Michael
authors.initials: M
authors.lastname: Drew
authors.forename: Douglas A
authors.initials: DA
authors.lastname: Craig
authors.forename: Bruno P
authors.initials: BP
authors.lastname: Guiard
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Guilloux
authors.forename: Roman P
authors.initials: RP
authors.lastname: Artymyshyn
authors.forename: Alain M
authors.initials: AM
authors.lastname: Gardier
authors.forename: Christophe
authors.initials: C
authors.lastname: Gerald
authors.forename: Irina A
authors.initials: IA
authors.lastname: Antonijevic
authors.forename: E David
authors.initials: ED
authors.lastname: Leonardo
authors.forename: René
authors.initials: R
authors.lastname: Hen
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D018687:Antidepressive Agents, Second-Generation / Q000627:therapeutic use*; D001007:Anxiety / Q000139:chemically induced / Q000178:diet therapy* / Q000473:pathology; D019390:Arrestins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism; D001973:Bromodeoxyuridine / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects / Q000528:radiation effects; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D003345:Corticosterone / Q000633:toxicity; D003863:Depression / Q000139:chemically induced / Q000188:drug therapy* / Q000473:pathology; D004195:Disease Models, Animal; D000089622:Doublecortin Domain Proteins; D004334:Drug Administration Schedule; D005106:Exploratory Behavior / Q000187:drug effects; D005247:Feeding Behavior / Q000187:drug effects; D005473:Fluoxetine / Q000627:therapeutic use*; D051960:GTP-Binding Protein alpha Subunit, Gi2 / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D006624:Hippocampus / Q000187:drug effects / Q000473:pathology / Q000528:radiation effects; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D055495:Neurogenesis / Q000187:drug effects* / Q000528:radiation effects; D009479:Neuropeptides / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011827:Radiation; D011930:Reaction Time / Q000187:drug effects; D000071560:beta-Arrestin 2; D000071557:beta-Arrestins
chemical_list: D018687:Antidepressive Agents, Second-Generation; C000605258:Arrb2 protein, mouse; D019390:Arrestins; D000089622:Doublecortin Domain Proteins; D008869:Microtubule-Associated Proteins; D009479:Neuropeptides; D012333:RNA, Messenger; D000071560:beta-Arrestin 2; D000071557:beta-Arrestins; D005473:Fluoxetine; D051960:GTP-Binding Protein alpha Subunit, Gi2; D001973:Bromodeoxyuridine; D003345:Corticosterone