Cognitive deficits in the rat chronic mild stress model for depression: relation to anhedonic-like responses

Research output: Contribution to journalJournal articleResearchpeer-review

  • Kim Henningsen
  • Andreasen T., Jesper
  • Elena V. Bouzinova
  • Magdalena Niepsuj Jayatissa
  • Morten S Jensen
  • John P Redrobe
  • Ove Wiborg
The chronic mild stress (CMS) protocol is widely used to evoke depressive-like behaviours in laboratory rats. The aim of the present study was to examine the effects of chronic stress on cognitive performance. About 70% of rats exposed to 7 weeks of chronic mild stress showed a gradual reduction in consumption of a sucrose solution, indicating an anhedonic-like state. The remaining rats did not reduce their sucrose intake, but appeared resilient to the stress-induced effects on sucrose intake. Cognitive profiling of the CMS rats revealed that chronic stress had a negative effect on performance in the spontaneous alternation test, possibly reflecting a deficit in working memory. This effect was independent of whether the stressed rats were anhedonic-like or stress-resilient as measured by their sucrose intake. CMS did not influence performance in passive avoidance and auditory cued fear conditioning, however, in rats displaying an anhedonic-like profile, CMS increased freezing behaviour in contextual fear conditioning.
Original languageEnglish
JournalBehavioural Brain Research
Volume198
Issue number1
Pages (from-to)136-41
Number of pages6
ISSN0166-4328
DOIs
Publication statusPublished - 2 Mar 2009

    Research areas

  • Acoustic Stimulation, Analysis of Variance, Animals, Avoidance Learning, Body Weight, Cognition, Conditioning, Classical, Cues, Depression, Disease Models, Animal, Exploratory Behavior, Fear, Feeding Behavior, Freezing Reaction, Cataleptic, Male, Memory, Movement, Rats, Rats, Wistar, Stress, Physiological, Sucrose

ID: 34329065