Brief fear preexposure facilitates subsequent fear conditioning

Neurosci Res. 2015 Jun;95:66-73. doi: 10.1016/j.neures.2015.02.001. Epub 2015 Feb 12.

Abstract

Post-traumatic stress disorder (PTSD) is an anxiety disorder that occurs following an unexpected exposure to a severe psychological event. A history of a brief trauma is reported to affect a risk for future PTSD development; however, little is known about the mechanisms by which a previous trauma exposure drives the sensitivity to a late-coming trauma. Using a mouse PTSD model, we found that a prior foot shock enhances contextual fear conditioning. This shock-induced facilitation of fear conditioning (i.e., priming effect) persisted for 7 days and was prevented by MK801, an N-methyl-D-aspartate receptor antagonist. Other types of trauma, such as forced swimming or tail pinch, did not induce a priming effect on fear conditioning. Thus, a trauma is unlikely generalized to modify the sensitivity to other traumatic experiences. The behavioral procedure employed in this study may be a useful tool to elucidate the etiology of PTSD.

Keywords: Fear conditioning; Mouse; N-methyl-d-aspartate receptor; Post traumatic stress disorder; Trauma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anxiety / psychology
  • Conditioning, Classical* / drug effects
  • Conditioning, Classical* / physiology
  • Dizocilpine Maleate / pharmacology
  • Electroshock
  • Excitatory Amino Acid Antagonists / pharmacology
  • Fear / physiology
  • Fear / psychology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Pain / psychology
  • Stress Disorders, Post-Traumatic / physiopathology
  • Stress Disorders, Post-Traumatic / psychology*
  • Stress, Psychological / physiopathology
  • Stress, Psychological / psychology

Substances

  • Excitatory Amino Acid Antagonists
  • Dizocilpine Maleate