title: NREM sleep hypersomnia and reduced sleep/wake continuity in a neuroendocrine mouse model of anxiety/depression based on chronic corticosterone administration.
abstract: Sleep/wake disorders are frequently associated with anxiety and depression and to elevated levels of cortisol. Even though these alterations are increasingly sought in animal models, no study has investigated the specific effects of chronic corticosterone (CORT) administration on sleep. We characterized sleep/wake disorders in a neuroendocrine mouse model of anxiety/depression, based on chronic CORT administration in the drinking water (35 μg/ml for 4 weeks, "CORT model"). The CORT model was markedly affected during the dark phase by non-rapid eye movement sleep (NREM) increase without consistent alteration of rapid eye movement (REM) sleep. Total sleep duration (SD) and sleep efficiency (SE) increased concomitantly during both the 24h and the dark phase, due to the increase in the number of NREM sleep episodes without a change in their mean duration. Conversely, the total duration of wake decreased due to a decrease in the mean duration of wake episodes despite an increase in their number. These results reflect hypersomnia by intrusion of NREM sleep during the active period as well as a decrease in sleep/wake continuity. In addition, NREM sleep was lighter, with an increased electroencephalogram (EEG) theta activity. With regard to REM sleep, the number and the duration of episodes decreased, specifically during the first part of the light period. REM and NREM sleep changes correlated respectively with the anxiety and the anxiety/depressive-like phenotypes, supporting the notion that studying sleep could be of predictive value for altered emotional behavior. The chronic CORT model in mice that displays hallmark characteristics of anxiety and depression provides an insight into understanding the changes in overall sleep architecture that occur under pathological conditions.
authors.affiliation: Univ Paris-Sud, EA3544, Faculté de Pharmacie, 92296 Châtenay-Malabry cedex, France. Electronic address: yannick.ledantec@gmail.com.
authors.forename: Y
authors.initials: Y
authors.lastname: Le Dantec
authors.affiliation: Univ Paris-Sud, EA3544, Faculté de Pharmacie, 92296 Châtenay-Malabry cedex, France.
authors.forename: G
authors.initials: G
authors.lastname: Hache
authors.affiliation: Univ Paris-Sud, EA3544, Faculté de Pharmacie, 92296 Châtenay-Malabry cedex, France.
authors.forename: J P
authors.initials: JP
authors.lastname: Guilloux
authors.affiliation: Univ Paris-Sud, EA3544, Faculté de Pharmacie, 92296 Châtenay-Malabry cedex, France.
authors.forename: B P
authors.initials: BP
authors.lastname: Guiard
authors.affiliation: Univ Paris-Sud, EA3544, Faculté de Pharmacie, 92296 Châtenay-Malabry cedex, France.
authors.forename: D J
authors.initials: DJ
authors.lastname: David
authors.affiliation: UMR975, CRicm - INSERM/CNRS/UPMC, Neurotransmetteurs et Sommeil, Faculté de Médecine Pitié-Salpêtrière, Université Pierre et Marie Curie - Paris VI, 91 boulevard de l'Hôpital, 75013 Paris, France.
authors.forename: J
authors.initials: J
authors.lastname: Adrien
authors.affiliation: Univ Paris-Sud, EA3544, Faculté de Pharmacie, 92296 Châtenay-Malabry cedex, France; Assistance Publique-Hôpitaux de Paris, Hôpital Antoine Béclère, Département de Physiologie, Centre de Médecine du Sommeil, 92141 Clamart cedex, France.
authors.forename: P
authors.initials: P
authors.lastname: Escourrou
mesh_terms: D000818:Animals; D001008:Anxiety Disorders / Q000503:physiopathology*; D001921:Brain / Q000503:physiopathology; D003345:Corticosterone; D003624:Darkness; D003866:Depressive Disorder / Q000503:physiopathology*; D004195:Disease Models, Animal; D006970:Disorders of Excessive Somnolence / Q000503:physiopathology*; D004569:Electroencephalography; D004644:Emotions; D008297:Male; D008810:Mice, Inbred C57BL; D017440:Photoperiod; D012895:Sleep, REM / Q000502:physiology; D013826:Theta Rhythm; D014851:Wakefulness
chemical_list: D003345:Corticosterone
keywords: anxiety/depression; behavior; corticosterone; hypersomnia; sleep disorders; sleep/wake continuity