title: Phosphorylation of cAMP response element-binding protein in the extended amygdala of male rats is induced by novel environment and attenuated by estrous female-bedding.
abstract: OBJECTIVE
  We examined whether female pheromone, which would be contained in female-soiled bedding, affected the expression of phosphorylated cAMP response element-binding protein-like (pCREB) immunoreactive cells in the extended amygdala.
  
  
  METHODS
  Male rats were exposed to following conditions: maintained in their home cage (home cage group), or relocated to a cage containing clean bedding (clean-bedding exposed group), ovariectomized (OVX) rat-soiled bedding (OVX-bedding exposed group) or estrogen-treated OVX rat-soiled bedding (OVX+E2-bedding exposed group). Rats were sacrificed 10-20 min after exposure and brain sections were subject to immunocytochemical processing.
  
  
  RESULTS
  In the medial subdivision of the bed nucleus of the stria terminalis (BST) and the central amygdala (CeA), the number of pCREB immunoreactive (pCREB-ir) cells in the clean-bedding exposed group was significantly larger than in the home cage group, while the number of pCREB-ir cells in the OVX+E2-bedding exposed group did not differ from that in the home cage group. The bedding soiled by OVX rats was less effective. No significant difference in the number of pCREB-ir cells was detected in the other regions of the extended amygdala among all groups.
  
  
  CONCLUSIONS
  The present study suggests that the exposure of clean bedding to male rats induces the expression of pCREB-ir in the medial BST and the CeA; exposure to female pheromone attenuates this expression.
authors: Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors: Shota
authors: S
authors: Nishitani
authors: Toshiya
authors: T
authors: Funabashi
authors: Kazuyuki
authors: K
authors: Shinohara
authors: Fukuko
authors: F
authors: Kimura
mesh_terms: D000679:Amygdala / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism*; D004967:Estrogens / Q000378:metabolism*; D005260:Female; D008297:Male; D009474:Neurons / Q000378:metabolism; D010766:Phosphorylation; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D017362:Cyclic AMP Response Element-Binding Protein; D004967:Estrogens; D016760:Proto-Oncogene Proteins c-fos