title: Vagus nerve stimulation ameliorated deficits in one-way active avoidance learning and stimulated hippocampal neurogenesis in bulbectomized rats.
abstract: BACKGROUND
  Vagus nerve stimulation (VNS) has been introduced as a therapeutic option for treatment-resistant depression. The neural and chemical mechanisms responsible for the effects of VNS are largely unclear.
  
  
  METHODS
  Bilateral removal of the olfactory bulbs (OBX) is a validated animal model in depression research. We studied the effects of vagus nerve stimulation (VNS) on disturbed one-way active avoidance learning and neurogenesis in the hippocampal dentate gyrus of rats.
  
  
  RESULTS
  After a stimulation period of 3 weeks, OBX rats acquired the learning task as controls. In addition, the OBX-related decrease of neuronal differentiated BrdU positive cells in the dentate gyrus was prevented by VNS.
  
  
  CONCLUSIONS
  This suggests that chronic VNS and changes in hippocampal neurogenesis induced by VNS may also account for the amelioration of behavioral deficits in OBX rats. To the best of our knowledge, this is the first report on the restorative effects of VNS on behavioral function in an animal model of depression that can be compared with the effects of antidepressants.
authors.affiliation: O.-v.-Guericke University, Faculty of Medicine, Institute of Pharmacology and Toxicology, Leipziger Str. 44, D-39120 Magdeburg, Germany.
authors.forename: Nils
authors.initials: N
authors.lastname: Gebhardt
authors.forename: Karl-Jürgen
authors.initials: KJ
authors.lastname: Bär
authors.forename: Michael K
authors.initials: MK
authors.lastname: Boettger
authors.forename: Gisela
authors.initials: G
authors.lastname: Grecksch
authors.forename: Gerburg
authors.initials: G
authors.lastname: Keilhoff
authors.forename: Rupert
authors.initials: R
authors.lastname: Reichart
authors.forename: Axel
authors.initials: A
authors.lastname: Becker
mesh_terms: D000818:Animals; D001362:Avoidance Learning / Q000502:physiology*; D003863:Depression / Q000628:therapy*; D004195:Disease Models, Animal; D005455:Fluorescent Antibody Technique; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D055495:Neurogenesis / Q000502:physiology*; D009830:Olfactory Bulb / Q000601:surgery; D051381:Rats; D017208:Rats, Wistar; D055536:Vagus Nerve Stimulation