title: Effects of chronic social defeat stress on behavior and choline acetyltransferase, 78-kDa glucose-regulated protein, and CCAAT/enhancer-binding protein (C/EBP) homologous protein in adult mice.
abstract: BACKGROUND
  Social defeat stress induces physiological and behavioral symptoms, including anxiety, anhedonia, immune deficits, and altered expression of key brain genes.
  
  
  OBJECTIVE
  The present study investigated the effects of social defeat stress on the behaviors and expressions of Chat, Grp78, and chop in the brains of adult mice.
  
  
  METHODS
  Adult mice were divided into susceptible and unsusceptible groups after 10 days of social defeat stress. In experiment 1, behavioral tests were conducted, and brains were processed for Western blotting at day 27 after stress. In experiment 2, social avoidance tests were conducted, and brains were processed for Western blotting at day 12 after stress.
  
  
  RESULTS
  The results indicate decreased and increased locomotion and anxiety behavior in all defeated mice. Decrease in social interaction, increased immobility, and impaired memory performance were only observed in susceptible mice. A decrease in the Chat level at days 12 and 27 was noted in the prefrontal cortex (PFC), amygdala (Amyg), and dorsal hippocampus (HIP) in defeated mice. The expression levels of Grp78 and chop measured on days 12 and 27 were significantly greater in the Amyg of susceptible mice. In the PFC and HIP, defeated mice displayed different patterns in the levels of Grp78 and chop expressions measured on days 12 and 27.
  
  
  CONCLUSIONS
  The present study demonstrated that chronic social defeat stress in mice produces stress-related behaviors. Different response patterns were noted for Grp78 and chop expression among the groups in terms of brain regions and time-course effects.
authors.affiliation: Department of Psychiatry, Chonbuk National University Medical School, Jeonju, Korea.
authors.forename: Tong
authors.initials: T
authors.lastname: Zhao
authors.forename: Guang-Biao
authors.initials: GB
authors.lastname: Huang
authors.forename: Sushma Shrestha
authors.initials: SS
authors.lastname: Muna
authors.forename: Tarique Rajasaheb
authors.initials: TR
authors.lastname: Bagalkot
authors.forename: Hong-Mei
authors.initials: HM
authors.lastname: Jin
authors.forename: Han-Jung
authors.initials: HJ
authors.lastname: Chae
authors.forename: Young-Chul
authors.initials: YC
authors.lastname: Chung
mesh_terms: D000679:Amygdala / Q000378:metabolism; D000818:Animals; D001007:Anxiety / Q000503:physiopathology; D001522:Behavior, Animal; D015153:Blotting, Western; D002795:Choline O-Acetyltransferase / Q000235:genetics* / Q000378:metabolism; D004291:Dominance-Subordination; D000091342:Endoplasmic Reticulum Chaperone BiP; D006360:Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism; D008124:Locomotion; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D017397:Prefrontal Cortex / Q000378:metabolism; D013315:Stress, Psychological / Q000503:physiopathology*; D013997:Time Factors; D051742:Transcription Factor CHOP / Q000235:genetics* / Q000378:metabolism
chemical_list: D000091342:Endoplasmic Reticulum Chaperone BiP; D006360:Heat-Shock Proteins; C000717248:Hspa5 protein, mouse; D051742:Transcription Factor CHOP; D002795:Choline O-Acetyltransferase