Three-dimensional distribution of Fos-positive neurons in the supramammillary nucleus of the rat exposed to novel environment.
Neurosci Res
; 64(4): 397-402, 2009 Aug.
Article
in En
| MEDLINE
| ID: mdl-19409426
ABSTRACT
The supramammillary nucleus (SuM) in the hypothalamus is proposed to regulate the function of the hippocampus through distinct fiber connection. Several investigations suggest that the SuM is relevant to anxiety and defensive behavior. Function of the SuM, however, is not known exactly. In order to demonstrate the spatial activation of the SuM in physiologically behaving rats, we investigated Fos induction in the SuM by exposure to novel environment. To correct uneven background in microscopic preparations, we applied a convolution filter, resulting in reliable automatic counting of Fos-positive neurons and analyzed the distribution of Fos-positive neurons in the whole region of SuM. A large number of Fos-positive neurons were observed throughout the entire SuM after rats exposed to a novel open field. A three-dimensional density map revealed that density of the Fos-positive neurons was highest in the medial SuM, especially in its core regions. Based on these results we suggest that the medial SuM modulates defensive behavior and that the lateral SuM modulates emotional and memory functions of the hippocampus.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Proto-Oncogene Proteins c-fos
/
Mammillary Bodies
/
Environment, Controlled
/
Exploratory Behavior
/
Hypothalamus, Posterior
/
Neurons
Limits:
Animals
Language:
En
Journal:
Neurosci Res
Journal subject:
NEUROLOGIA
Year:
2009
Document type:
Article
Affiliation country:
Japón