Long-term potentiation in frontal cortex: Role of NMDA-modulated polysynaptic excitatory pathways

Academic Article


  • The present study examined the role of N-methyl-d-aspartic acid (NMDA) receptors in synaptic plasticity in regular-spiking cells of rat frontal cortex. Intracortical stimulation, at levels subthreshold for elicitation of action potentials, evoked a late excitatory postsynaptic potential (EPSP) in layer II III neurons that was sensitive to the selective NMDA antagonist d-2-amino-5-phosphonovaleric acid (APV). This late EPSP showed marked short-term frequency-dependent depression, suggesting that it is polysynaptic in origin. Polysynaptic late EPSPs were selectively enhanced following high-frequency stimulation. This sustained increase in synaptic efficacy, or long-term potentiation, was expressed in regular spiking cells and appeared to result from activation of NMDA receptors on excitatory interneurons. These data demonstrate the existence of an NMDA-modulated polysynaptic circuit in the neocortex which displays several types of use-dependent plasticity. © 1989.
  • Authors

    Published In

    Digital Object Identifier (doi)

    Author List

  • Sutor B; Hablitz JJ
  • Start Page

  • 111
  • End Page

  • 117
  • Volume

  • 97
  • Issue

  • 1-2