Increased expression level of corticotropin-releasing hormone in the amygdala and in the hypothalamus in rats exposed to chronic unpredictable mild stress.
OBJECTIVE
Corticotropin-releasing hormone (CRH) plays an important role in neuroendocrine, autonomic and behavioral responses to stressors. In the present study, the effect of chronic unpredictable mild stress (CUMS) on CRH neurons was investigated in rat brain.


METHODS
The rats were exposed to one of the stressors each day for 21 d. Immunostaining was performed to detect the CRH-positive neurons in the paraventricular nucleus (PVN) of the hypothalamus and in amygdala.


RESULTS
After the stress protocol, the animals showed a reduction in body weight gain as well as reduced sucrose preference and locomotor activity. Interestingly, the CRH neurons in both PVN and central nucleus of the amygdala (CeA) were stimulated by CUMS. The densities of CRH-containing neurons in both PVN and CeA were significantly higher than those in control group.


CONCLUSIONS
The CRH systems in PVN and CeA may both contribute to depression-like behaviors during CUMS.
Wang
Shan-Shan
SS
Department of Neurology, Clinical Division of Nanlou, Chinese PLA General Hospital, Beijing, China.
Yan
Xue-Bo
XB
Hofman
Michel A
MA
Swaab
Dick F
DF
Zhou
Jiang-Ning
JN
D000679:Amygdala / Q000166:cytology / Q000378:metabolism*; D000704:Analysis of Variance; D000818:Animals; D001835:Body Weight / Q000502:physiology; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism*; D005106:Exploratory Behavior / Q000502:physiology; D005508:Food Deprivation / Q000502:physiology; D005518:Food Preferences / Q000502:physiology; D008297:Male; D009043:Motor Activity / Q000502:physiology; D010286:Paraventricular Hypothalamic Nucleus / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013312:Stress, Physiological / Q000502:physiology*; D013395:Sucrose / Q000008:administration & dosage; D013549:Sweetening Agents / Q000008:administration & dosage; D013550:Swimming / Q000523:psychology; D015854:Up-Regulation / Q000502:physiology*
D013549:Sweetening Agents; D013395:Sucrose; D003346:Corticotropin-Releasing Hormone