title: Maternal deprivation induces depressive-like behaviours only in female rats.
abstract: Maternal deprivation (MD) has been developed to study the effects of early adverse experiences on behaviour and neurobiology. It has been proposed to represent a potential animal model of major depression. The purpose of our study was to examine the responses induced by MD in male and female adult Long-Evans rats in tasks designed to explore depressive-like behaviours (forced swimming test (FST), repeated open space swim test (OSST), sucrose solution consumption) and in the novel object recognition and object location tasks. A consistent sexual dimorphism was observed in the responses of male and female rats that underwent MD. In male rats, MD led to increased transitions between behaviours in the FST and increased consumption and preference for sucrose (1%) in comparison with non-deprived rats. In female rats, MD induced a decreased swimming activity on the second day of the OSST and reduced the cognitive performance in an object location task. In both sexes, MD did not alter the swimming activity in the FST and the performance in a novel object recognition task. These divergent responses in male and female rats can be related to the gender differences which exist in depression. However, due to the low amplitude of responses obtained in our study, the MD model in Long-Evans rats does not seem to mimic symptoms of major depression. In contrast, our present results suggest the use of the MD model, especially in females, as a model of the dysthymia, a mild chronic-depressive condition, which has been related to poorer maternal relationship.
authors.affiliation: INSERM, UMRS 952, Physiopathologie des Maladies du Système nerveux Central, UPMC Paris VI, 9 quai Saint Bernard, Paris, France.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Mourlon
authors.forename: Aurélie
authors.initials: A
authors.lastname: Baudin
authors.forename: Orianne
authors.initials: O
authors.lastname: Blanc
authors.forename: Andrea
authors.initials: A
authors.lastname: Lauber
authors.forename: Bruno
authors.initials: B
authors.lastname: Giros
authors.forename: Laurent
authors.initials: L
authors.lastname: Naudon
authors.forename: Valérie
authors.initials: V
authors.lastname: Daugé
mesh_terms: D000818:Animals; D003863:Depression / Q000523:psychology*; D004195:Disease Models, Animal; D005106:Exploratory Behavior; D005260:Female; D005518:Food Preferences / Q000523:psychology; D008297:Male; D008426:Maternal Deprivation; D008568:Memory; D051381:Rats; D020318:Rats, Long-Evans; D012727:Sex Characteristics; D013550:Swimming / Q000523:psychology