Phosphorylation of ERK/MAP kinase is required for long-term potentiation in anatomically restricted regions of the lateral amygdala in vivo.
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.
Schafe
Glenn E
GE
Department of Psychology and Interdepartmental Neuroscience Program, Yale University, New Haven, Connecticut 06520, USA. glenn.schafe@yale.edu
Swank
Michael W
MW
Rodrigues
Sarina M
SM
Debiec
Jacek
J
Doyère
Valérie
V
D000679:Amygdala / Q000201:enzymology / Q000502:physiology*; D000818:Animals; D001306:Auditory Pathways / Q000502:physiology; D002070:Butadienes / Q000008:administration & dosage / Q000494:pharmacology; D004558:Electric Stimulation / Q000379:methods; D004789:Enzyme Activation / Q000502:physiology; D004791:Enzyme Inhibitors / Q000008:administration & dosage / Q000494:pharmacology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D007150:Immunohistochemistry; D017774:Long-Term Potentiation / Q000187:drug effects / Q000502:physiology*; D008297:Male; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009473:Neuronal Plasticity / Q000502:physiology; D009570:Nitriles / Q000008:administration & dosage / Q000494:pharmacology; D010766:Phosphorylation; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000502:physiology; D013569:Synapses / Q000502:physiology; D013788:Thalamus / Q000502:physiology; D013997:Time Factors; D014018:Tissue Distribution
D002070:Butadienes; D004791:Enzyme Inhibitors; D009570:Nitriles; C113580:U 0126; D048049:Extracellular Signal-Regulated MAP Kinases; D020928:Mitogen-Activated Protein Kinases