Long-term aversive taste memory requires insular and amygdala protein degradation

Neurobiol Learn Mem. 2011 Mar;95(3):311-5. doi: 10.1016/j.nlm.2010.12.010. Epub 2010 Dec 28.

Abstract

Some reports have shown that the ubiquitin-proteasome system (UPS) is necessary to degrade repressor factors to produce new proteins essential to memory consolidation. Furthermore, recent evidence suggests that memory updating also relies on protein degradation through the UPS. To evaluate whether degradation of proteins is part of the cellular events needed for long-term storage of taste aversion, we injected lactacystin--an UPS inhibitor--into the amygdala and/or insular cortex 30 min before the first or second training trials. The results revealed that degradation of proteins in either the amygdala or insular cortex suffices for long-term stabilization of first-time encounter taste aversion. On the other hand, lactacystin applied in the insula, but not in the amygdala, before the second training prevented long-term storage of updated information. Our results support that degradation of proteins by means of the UPS is required every time taste aversion is to be stored in long-term memory.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcysteine / analogs & derivatives*
  • Acetylcysteine / pharmacology
  • Amygdala / drug effects
  • Amygdala / metabolism*
  • Animals
  • Association Learning / drug effects
  • Association Learning / physiology
  • Avoidance Learning / drug effects
  • Avoidance Learning / physiology*
  • Cerebral Cortex / drug effects
  • Cerebral Cortex / metabolism*
  • Cysteine Proteinase Inhibitors / pharmacology*
  • Male
  • Memory, Long-Term / drug effects
  • Memory, Long-Term / physiology*
  • Nerve Tissue Proteins / metabolism
  • Proteasome Endopeptidase Complex / metabolism
  • Proteasome Inhibitors
  • Rats
  • Rats, Wistar
  • Taste
  • Ubiquitin / antagonists & inhibitors
  • Ubiquitin / metabolism

Substances

  • Cysteine Proteinase Inhibitors
  • Nerve Tissue Proteins
  • Proteasome Inhibitors
  • Ubiquitin
  • lactacystin
  • Proteasome Endopeptidase Complex
  • Acetylcysteine