Distinct populations of NMDA receptors at subcortical and cortical inputs to principal cells of the lateral amygdala

Marc G. Weisskopf, Joseph E. Ledoux

Research output: Contribution to journalArticle

Abstract

Fear conditioning involves the transmission of sensory stimuli to the amygdala from the thalamus and cortex. These input synapses are prime candidates for sites of plasticity critical to the learning in fear conditioning. Because N-methyl-D-aspartate (NMDA)-dependent mechanisms have been implicated in fear learning, we investigated the contribution of NMDA receptors to synaptic transmission at putative cortical and thalamic inputs using visualized whole cell recording in amygdala brain slices. Whereas NMDA receptors are present at both of these pathways, differences were observed. First, the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-receptor- mediated component of the synaptic response, relative to the NMDA component, is smaller at thalamic than cortical input synapses. Second, thalamic NMDA responses are more sensitive to Mg2+. These findings suggest that there are distinct populations of NMDA receptors at cortical and thalamic inputs to the lateral amygdala. Differences such as these might underlie unique contributions of the two pathways to fear conditioning.

Original languageEnglish (US)
Pages (from-to)930-934
Number of pages5
JournalJournal of neurophysiology
Volume81
Issue number2
DOIs
StatePublished - Jan 1 1999

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ASJC Scopus subject areas

  • Neuroscience(all)
  • Physiology

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