title: Chronic social stress does not affect behavioural habituation in male CD1 mice.
abstract: Various protocols to induce chronic stress in rodents are being used to determine the effects and underlying mechanisms of prolonged stress experience. Recently, a novel chronic social stress (CSS) protocol has been developed for mice where social instability in adolescence and early adulthood is induced. This protocol has been shown to cause an increase in HPA-axis activity and acute avoidance behaviour in the elevated plus maze. The aim of the present study was to investigate the effect of this CSS protocol on habituation to an initially novel environment in CD1 mice, since it has been shown that initially high avoidance behaviour in mice can still be followed by rapid habituation, pointing towards an adaptive response. One group of male mice, the CSS group, was exposed to the CSS protocol for 7 weeks and we compared their behavioural and physiological responses with male mice that were housed in a stable social group, the SH group. The results reveal a decrease in body weight gain and fur condition, changes in adrenal weight and decreased GR mRNA expression in the CA1 and the dentate gyrus of the hippocampus in chronically stressed CD1 animals. Irrespective of such evidence for a significantly stressful effect of the protocol, CD 1 mice, after termination of the stress procedure, revealed habituation profiles that matched those of control animals. We conclude that the physiological and central-nervous effects caused by a CSS procedure as used in this experiment fall within the coping capacities of CD1 mice at the behavioural level.
authors.affiliation: Department of Animals in Science and Society, Division of Animal Welfare and Laboratory Animal Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands; Rudolf Magnus Institute of Neuroscience, Utrecht, The Netherlands.
authors.forename: Hetty
authors.initials: H
authors.lastname: Boleij
authors.affiliation: Department of Animals in Science and Society, Division of Animal Welfare and Laboratory Animal Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Jeroen
authors.initials: J
authors.lastname: Willems
authors.affiliation: Department of Animals in Science and Society, Division of Animal Welfare and Laboratory Animal Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Marieke
authors.initials: M
authors.lastname: Leijten
authors.affiliation: Department of Animals in Science and Society, Division of Animal Welfare and Laboratory Animal Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands; Rudolf Magnus Institute of Neuroscience, Utrecht, The Netherlands.
authors.forename: José
authors.initials: J
authors.lastname: van't Klooster
authors.affiliation: Department of Animals in Science and Society, Division of Animal Welfare and Laboratory Animal Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands; Rudolf Magnus Institute of Neuroscience, Utrecht, The Netherlands.
authors.forename: Heidi
authors.initials: H
authors.lastname: Lesscher
authors.affiliation: Department of Animals in Science and Society, Division of Animal Welfare and Laboratory Animal Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands; Rudolf Magnus Institute of Neuroscience, Utrecht, The Netherlands.
authors.forename: Susanne
authors.initials: S
authors.lastname: Kirchhoff
authors.affiliation: Department of Animals in Science and Society, Division of Animal Welfare and Laboratory Animal Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands; Rudolf Magnus Institute of Neuroscience, Utrecht, The Netherlands.
authors.forename: Marla
authors.initials: M
authors.lastname: Lavrijsen
authors.affiliation: Department of Animals in Science and Society, Division of Animal Welfare and Laboratory Animal Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands; Rudolf Magnus Institute of Neuroscience, Utrecht, The Netherlands. Electronic address: s.s.arndt@uu.nl.
authors.forename: Saskia S
authors.initials: SS
authors.lastname: Arndt
authors.affiliation: Department of Animals in Science and Society, Division of Animal Welfare and Laboratory Animal Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands; Rudolf Magnus Institute of Neuroscience, Utrecht, The Netherlands.
authors.forename: Frauke
authors.initials: F
authors.lastname: Ohl
mesh_terms: D000818:Animals; D001835:Body Weight; D003345:Corticosterone / Q000097:blood; D005106:Exploratory Behavior; D006185:Habituation, Psychophysiologic; D006624:Hippocampus / Q000378:metabolism; D008297:Male; D051379:Mice; D009043:Motor Activity; D011965:Receptors, Glucocorticoid / Q000378:metabolism; D018161:Receptors, Mineralocorticoid / Q000378:metabolism; D012919:Social Behavior; D013315:Stress, Psychological / Q000378:metabolism / Q000503:physiopathology / Q000523:psychology*
chemical_list: D011965:Receptors, Glucocorticoid; D018161:Receptors, Mineralocorticoid; D003345:Corticosterone
keywords: CDI mouse; Chronic stress; Habituation; In situ hybridization; Modified holeboard; Social instability