In vivo long-term potentiation in the insular cortex: NMDA receptor dependence

Brain Res. 1998 Jan 1;779(1-2):314-9. doi: 10.1016/s0006-8993(97)01175-x.


It has been demonstrated that the insular cortex (IC) plays an important role in the acquisition and storage of different aversive motivated learning tasks like conditioned taste aversion, spatial maze and inhibitory avoidance. It is of particular interest to investigate whether activity-dependent modification of synaptic efficacy, a presumptive mechanism for learning and memory, is present in this cortical region. Here, we address this issue by examining the induction of synaptic plasticity, long-term potentiation (LTP) in in vivo preparations. The results showed that high frequency stimulation of the basolateral amygdaloid nucleus (Bla) induced LTP in the IC. The LTP induced by tetanus was blocked by application of the N-methyl-D-aspartate (NMDA) receptor antagonists CPP and MK-801, indicating that NMDA receptors were responsible for its induction. These results suggest that in vivo tetanus induced LTP of the Bla-IC projection is a possible mechanism for the memory-related functions performed by the IC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amygdala / drug effects
  • Amygdala / physiology*
  • Analysis of Variance
  • Animals
  • Avoidance Learning / physiology*
  • Electric Stimulation
  • Excitatory Amino Acid Antagonists / pharmacology
  • Excitatory Postsynaptic Potentials / drug effects
  • Excitatory Postsynaptic Potentials / physiology
  • Long-Term Potentiation*
  • Male
  • Neural Pathways / drug effects
  • Neural Pathways / physiology
  • Rats
  • Rats, Wistar
  • Receptors, N-Methyl-D-Aspartate / antagonists & inhibitors
  • Receptors, N-Methyl-D-Aspartate / physiology*
  • Temporal Lobe / drug effects
  • Temporal Lobe / physiology*
  • Tetany


  • Excitatory Amino Acid Antagonists
  • Receptors, N-Methyl-D-Aspartate