Abstract
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 language | English |
|---|---|
| Journal | Behavioural Brain Research |
| Volume | 198 |
| Issue number | 1 |
| Pages (from-to) | 136-41 |
| Number of pages | 6 |
| ISSN | 0166-4328 |
| DOIs | |
| Publication status | Published - 2 Mar 2009 |
Keywords
- 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