title: Chronic variable stress exposure in male Wistar rats affects the first step of olfactory detection.
abstract: For most animal species, olfaction plays a paramount role in their perception of the environment. Odours are initially detected in neurons located in the olfactory mucosa. This tissue is regulated by several physiological signals and can be altered in pathology. A number of clinical studies suggest an association between depressive disorders and olfactory sensory loss. In rodents, depressive-like states can be observed in models of chronic stress. We tested the hypothesis that olfactory function might be altered in a rat model of depression, induced by chronic variable stress (CVS). While CVS rats exhibited several symptoms consistent with chronic stress exposure and depressive-like states (increased sucrose intake in sucrose preference test, increased immobility in forced swim test, hyperlocomotion), their odorant responses recorded at the olfactory mucosa level by electro-olfactogram were decreased. In addition we observed increased apoptosis markers in the olfactory mucosa using Western Blot. Our data are consistent with reduced olfactory capacities in a laboratory rat model of chronic stress and depression, in agreement with human clinical data; this warrants further mechanistic studies. Furthermore, this works raises the possibility that altered olfactory function might be a confounding factor in the behavioural testing of chronically stressed or depressed rats.
authors.affiliation: Institut National de la Recherche Agronomique (INRA), UR 1197 NeuroBiologie de l'Olfaction, Domaine de Vilvert, Jouy-en-Josas, France.
authors.forename: Aurélien
authors.initials: A
authors.lastname: Raynaud
authors.affiliation: Institut National de la Recherche Agronomique (INRA), UR 1197 NeuroBiologie de l'Olfaction, Domaine de Vilvert, Jouy-en-Josas, France; Université de Versailles St-Quentin en Yvelines, Versailles, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Meunier
authors.affiliation: Institut National de la Recherche Agronomique (INRA), UR 1197 NeuroBiologie de l'Olfaction, Domaine de Vilvert, Jouy-en-Josas, France.
authors.forename: Adrien
authors.initials: A
authors.lastname: Acquistapace
authors.affiliation: Institut National de la Recherche Agronomique (INRA), UR 1197 NeuroBiologie de l'Olfaction, Domaine de Vilvert, Jouy-en-Josas, France. Electronic address: vincent.bombail@jouy.inra.fr.
authors.forename: Vincent
authors.initials: V
authors.lastname: Bombail
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D002908:Chronic Disease; D003866:Depressive Disorder / Q000473:pathology / Q000503:physiopathology*; D019422:Dietary Sucrose; D004195:Disease Models, Animal; D005247:Feeding Behavior / Q000502:physiology; D008297:Male; D009043:Motor Activity / Q000502:physiology; D009474:Neurons / Q000502:physiology; D009831:Olfactory Mucosa / Q000473:pathology / Q000503:physiopathology*; D017208:Rats, Wistar; D012903:Smell / Q000502:physiology*; D013315:Stress, Psychological / Q000473:pathology / Q000503:physiopathology*; D013550:Swimming / Q000502:physiology
chemical_list: D019422:Dietary Sucrose
keywords: Chronic stress; Depression; Odorant response; Olfactory epithelium