Roles of p75(NTR), long-term depression, and cholinergic transmission in anxiety and acute stress coping

Biol Psychiatry. 2012 Jan 1;71(1):75-83. doi: 10.1016/j.biopsych.2011.08.014. Epub 2011 Oct 5.

Abstract

Background: Stress is causally associated with anxiety. Although the underlying cellular mechanisms are not well understood, the basal forebrain cholinergic neurons have been implicated in stress response. p75(NTR) is a panneurotrophin receptor expressed almost exclusively in basal forebrain cholinergic neurons in adult brain. This study investigated whether and how p75(NTR), via regulation of the cholinergic system and hippocampal synaptic plasticity, influences stress-related behaviors.

Methods: We used a combination of slice electrophysiology, behavioral analyses, pharmacology, in vivo microdialysis, and neuronal activity mapping to assess the role of p75(NTR) in mood and stress-related behaviors and its underlying cellular and molecular mechanisms.

Results: We show that acute stress enables hippocampal long-term depression (LTD) in adult wild-type mice but not in mice lacking p75(NTR). The p75(NTR) mutant mice also exhibit two distinct behavioral impairments: baseline anxiety-like behavior and a deficit in coping with and recovering from stressful situations. Blockade of stress-enabled LTD with a GluA2-derived peptide impaired stress recovery without affecting baseline anxiety. Pharmacological manipulations of cholinergic transmission mimicked the p75(NTR) perturbation in both baseline anxiety and responses to acute stress. Finally, we show evidence of misregulated cholinergic signaling in animals with p75(NTR) deletion.

Conclusions: Our results suggest that loss of p75(NTR) leads to changes in hippocampal cholinergic signaling, which may be involved in regulation of stress-enabled hippocampal LTD and in modulating behaviors related to stress and anxiety.

Publication types

  • Research Support, N.I.H., Intramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcholine / metabolism*
  • Adaptation, Psychological / drug effects
  • Adaptation, Psychological / physiology
  • Analysis of Variance
  • Animals
  • Anxiety / genetics*
  • Anxiety / pathology
  • Anxiety / physiopathology
  • Biophysics
  • Cholinergic Agents / pharmacology
  • Disease Models, Animal
  • Dose-Response Relationship, Drug
  • Electric Stimulation
  • Exploratory Behavior / drug effects
  • Exploratory Behavior / physiology
  • Hippocampus / drug effects
  • Hippocampus / physiopathology*
  • In Vitro Techniques
  • Long-Term Synaptic Depression / drug effects
  • Long-Term Synaptic Depression / genetics*
  • Long-Term Synaptic Depression / physiology
  • Male
  • Maze Learning / drug effects
  • Maze Learning / physiology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Microdialysis
  • Microinjections
  • N-Methylaspartate / pharmacology
  • Patch-Clamp Techniques
  • Proto-Oncogene Proteins c-fos / metabolism
  • Receptors, Nerve Growth Factor / deficiency
  • Receptors, Nerve Growth Factor / metabolism*
  • Stress, Psychological / genetics*
  • Stress, Psychological / pathology
  • Stress, Psychological / physiopathology
  • Time Factors

Substances

  • Cholinergic Agents
  • Proto-Oncogene Proteins c-fos
  • Receptors, Nerve Growth Factor
  • Ngfr protein, mouse
  • N-Methylaspartate
  • Acetylcholine