title: Acute stress exposure preceding global brain ischemia accelerates decreased doublecortin expression in the rat retrosplenial cortex.
abstract: BACKGROUND
  Psychological distress is a risk factor of stroke in humans and worsens the behavioral and neurological outcomes. In rats, acute stress exposure preceding ischemic events attenuates learning and memory. The retrosplenial cortex (RS) plays an important role in these functions, and global brain ischemia (GBI) or acute stress exposure can induce a decrease in expression of the immature neuronal marker, doublecortin (DCX), in the RS. However, little is known about the DCX expression in the RS after stress exposure prior to GBI.
  
  
  METHODS
  Eighteen male Sprague-Dawley rats were used. Acute stress exposure was applied as the forced swim paradigm and GBI was induced by bilateral common carotid arterial occlusion for 10 min. The rats were divided into three groups: GBI model preconditioned by stress (n = 6, Group P), GBI model preconditioned by non-stress (n = 6, Group G), and controls (n = 6, Group C). We performed immunohistochemistry to observe and analyze the DCX-expressing cells and Fluoro-Jade B (FJB) staining to detect cell death in the RS after GBI in each group.
  
  
  RESULTS
  The total number of DCX-expressing cells was 1,032, 1,219, and 1,904 in Group P, Group G, and Group C, respectively. The mean number of DCX-expressing cells per unit area was significantly lower in Group P and Group G than in Group C (P < 0.001). Moreover, the number was significantly lower in Group P than in Group G (P < 0.05). In each group, no FJB positive cells were observed.
  
  
  CONCLUSIONS
  DCX plays an important role in various cytoskeletal changes. Preconditioning by acute stress exposure accelerated the decrease in DCX expression in the RS after GBI.
authors.affiliation: Division of Neurosurgery, Department of Neurological Surgery, Nihon University School of Medicine, 30-1 Oyaguchikamicho, Itabashi-ku, 173-8610, Tokyo, Japan. nkutsuna@yahoo.co.jp.
authors.forename: Nobuo
authors.initials: N
authors.lastname: Kutsuna
authors.affiliation: Division of Neurosurgery, Department of Neurological Surgery, Nihon University School of Medicine, 30-1 Oyaguchikamicho, Itabashi-ku, 173-8610, Tokyo, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Eriguchi
authors.affiliation: Division of Neurosurgery, Department of Neurological Surgery, Nihon University School of Medicine, 30-1 Oyaguchikamicho, Itabashi-ku, 173-8610, Tokyo, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Oshima
authors.affiliation: Division of Neurosurgery, Department of Neurological Surgery, Nihon University School of Medicine, 30-1 Oyaguchikamicho, Itabashi-ku, 173-8610, Tokyo, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Suma
authors.affiliation: Division of Optical Brain Engineering, Department of Neurological Surgery, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Sakatani
authors.affiliation: Division of Neurosurgery, Department of Neurological Surgery, Nihon University School of Medicine, 30-1 Oyaguchikamicho, Itabashi-ku, 173-8610, Tokyo, Japan.
authors.forename: Atsuo
authors.initials: A
authors.lastname: Yoshino
authors.affiliation: Division of Neurosurgery, Department of Neurological Surgery, Nihon University School of Medicine, 30-1 Oyaguchikamicho, Itabashi-ku, 173-8610, Tokyo, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Katayama
mesh_terms: D000818:Animals; D002545:Brain Ischemia / Q000378:metabolism* / Q000473:pathology; D016923:Cell Death / Q000502:physiology; D002540:Cerebral Cortex / Q000378:metabolism* / Q000473:pathology; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D008297:Male; D008869:Microtubule-Associated Proteins / Q000096:biosynthesis*; D009479:Neuropeptides / Q000096:biosynthesis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D040701:Stress Disorders, Traumatic, Acute / Q000378:metabolism* / Q000473:pathology
chemical_list: C000714328:DCX protein, human; C000714848:Dcx protein, rat; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D008869:Microtubule-Associated Proteins; D009479:Neuropeptides