Pre- and posttraining infusion of N-methyl-D-aspartate receptor antagonists into the amygdala impair memory in an inhibitory avoidance task

Behav Neurosci. 1994 Apr;108(2):241-53. doi: 10.1037//0735-7044.108.2.241.


Involvement of amygdaloid N-methyl-D-aspartate (NMDA) receptors in memory processes was investigated. Rats with cannulas implanted in the basolateral amygdala were trained on a 1 trial step-through inhibitory avoidance task and tested for 24-hr retention. Pretraining infusion of 2-amino-5-phosphonovaleric acid (APV) into the amygdala, but not striatum or hippocampus, produced a dose-dependent retention deficit, which was attenuated by immediate posttraining intra-amygdala infusion of NMDA. Posttraining APV infusion also caused a dose- and time-dependent retention deficit. Pretest APV infusion had no effect on performance in the retention test. Further, pre- or posttraining infusion of 5.0 micrograms APV failed to affect acquisition and retention in the Morris water maze task. These findings suggest that amygdala NMDA receptors are normally activated by aversive training and play a critical role in memory formation for affective experience.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 2-Amino-5-phosphonovalerate / pharmacology*
  • Amygdala / drug effects*
  • Animals
  • Avoidance Learning / drug effects*
  • Brain Mapping
  • Conditioning, Classical / drug effects
  • Dose-Response Relationship, Drug
  • Electroshock
  • Escape Reaction / drug effects
  • Fear / drug effects*
  • Male
  • Mental Recall / drug effects*
  • Neural Inhibition / drug effects*
  • Orientation / drug effects
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, N-Methyl-D-Aspartate / antagonists & inhibitors*
  • Retention, Psychology / drug effects


  • Receptors, N-Methyl-D-Aspartate
  • 2-Amino-5-phosphonovalerate