Phosphorylation of ERK/MAP kinase is required for long-term potentiation in anatomically restricted regions of the lateral amygdala in vivo

Learn Mem. 2008 Jan 28;15(2):55-62. doi: 10.1101/lm.746808. Print 2008 Feb.


We have previously shown that the extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/ MAPK) is transiently activated in anatomically restricted regions of the lateral amygdala (LA) following Pavlovian fear conditioning and that blockade of ERK/MAPK activation in the LA impairs both fear memory consolidation and long-term potentiation (LTP) in the amygdala, in vitro. The present experiments evaluated the role of the ERK/MAPK signaling cascade in LTP at thalamo-LA input synapses, in vivo. We first show that ERK/MAPK is transiently activated/phosphorylated in the LA at 5 min, but not 15 or 60 min, after high-frequency, but not low-frequency, stimulation of the auditory thalamus. ERK activation induced by LTP-inducing stimulation was anatomically restricted to the same regions of the LA previously shown to exhibit ERK regulation following fear conditioning. We next show that intra-LA infusion of U0126, an inhibitor of ERK/MAPK activation, impairs LTP at thalamo-LA input synapses. Collectively, results demonstrate that ERK/MAPK activation is necessary for synaptic plasticity in anatomically defined regions of the LA, in vivo.

Publication types

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

MeSH terms

  • Amygdala / enzymology
  • Amygdala / physiology*
  • Animals
  • Auditory Pathways / physiology
  • Butadienes / administration & dosage
  • Butadienes / pharmacology
  • Electric Stimulation / methods
  • Enzyme Activation / physiology
  • Enzyme Inhibitors / administration & dosage
  • Enzyme Inhibitors / pharmacology
  • Extracellular Signal-Regulated MAP Kinases / antagonists & inhibitors
  • Extracellular Signal-Regulated MAP Kinases / metabolism*
  • Immunohistochemistry
  • Long-Term Potentiation / drug effects
  • Long-Term Potentiation / physiology*
  • Male
  • Mitogen-Activated Protein Kinases / antagonists & inhibitors
  • Mitogen-Activated Protein Kinases / metabolism*
  • Neuronal Plasticity / physiology
  • Nitriles / administration & dosage
  • Nitriles / pharmacology
  • Phosphorylation
  • Rats
  • Rats, Sprague-Dawley
  • Signal Transduction / physiology
  • Synapses / physiology
  • Thalamus / physiology
  • Time Factors
  • Tissue Distribution


  • Butadienes
  • Enzyme Inhibitors
  • Nitriles
  • U 0126
  • Extracellular Signal-Regulated MAP Kinases
  • Mitogen-Activated Protein Kinases