Repeated Short-term (2hx14d) Emotional Stress Induces Lasting Depression-like Behavior in Mice.
- Author:
Kyoung Shim KIM
1
;
Hye Joo KWON
;
In Sun BAEK
;
Pyung Lim HAN
Author Information
- Publication Type:Original Article
- Keywords: emotional stress; anxiety; depression; behavior
- MeSH: Animals; Anxiety; Depression; Glucocorticoids; Imipramine; Mice; Risk Factors; Stress, Psychological; Water
- From:Experimental Neurobiology 2012;21(1):16-22
- CountryRepublic of Korea
- Language:English
- Abstract: Chronic behavioral stress is a risk factor for depression. To understand chronic stress effects and the mechanism underlying stress-induced emotional changes, various animals model have been developed. We recently reported that mice treated with restraints for 2 h daily for 14 consecutive days (2h-14d or 2hx14d) show lasting depression-like behavior. Restraint provokes emotional stress in the body, but the nature of stress induced by restraints is presumably more complex than emotional stress. So a question remains unsolved whether a similar procedure with "emotional" stress is sufficient to cause depression-like behavior. To address this, we examined whether "emotional" constraints in mice treated for 2hx14d by enforcing them to individually stand on a small stepping platform placed in a water bucket with a quarter full of water, and the stress evoked by this procedure was termed "water-bucket stress". The water-bucket stress activated the hypothalamus-pituitary-adrenal gland (HPA) system in a manner similar to restraint as evidenced by elevation of serum glucocorticoids. After the 2hx14d water-bucket stress, mice showed behavioral changes that were attributed to depression-like behavior, which was stably detected >3 weeks after last water-bucket stress endorsement. Administration of the anti-depressant, imipramine, for 20 days from time after the last emotional constraint completely reversed the stress-induced depression-like behavior. These results suggest that emotional stress evokes for 2hx14d in mice stably induces depression-like behavior in mice, as does the 2hx14d restraint.
