Excitatory amino acid receptors involved in primary afferent-evoked polysynaptic EPSPs of substantia gelatinosa neurons in the adult rat spinal cord slice

Neurosci Lett. 1992 Aug 31;143(1-2):131-4. doi: 10.1016/0304-3940(92)90249-7.

Abstract

Intracellular recordings were made from substantia gelatinosa (SG) neurons in spinal cord slices to determine a subclass of excitatory amino acid receptors involved in polysynaptic excitatory postsynaptic potentials (EPSPs). In the majority of neurons, polysynaptic EPSPs evoked by A delta fiber were not affected by 2-amino-5-phosphonovaleric acid (APV), while all EPSPs including monosynaptic EPSPs were depressed by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). All spontaneous EPSPs were blocked by CNQX, while spontaneous EPSPs in a few SG neurons were attenuated by APV. These observations suggest that polysynaptic EPSPs evoked through A delta fibers are predominantly mediated by activation of the non-N-methyl-D-aspartate (non-NMDA) receptor subclass.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 2-Amino-5-phosphonovalerate / pharmacology
  • 6-Cyano-7-nitroquinoxaline-2,3-dione
  • Afferent Pathways / physiology
  • Animals
  • Evoked Potentials / drug effects*
  • Neurons / drug effects
  • Neurons / physiology*
  • Quinoxalines / pharmacology
  • Rats
  • Receptors, AMPA
  • Receptors, Amino Acid / physiology*
  • Receptors, Glutamate / drug effects
  • Receptors, Glutamate / physiology*
  • Receptors, Kainic Acid
  • Receptors, N-Methyl-D-Aspartate / physiology
  • Substantia Gelatinosa / cytology
  • Substantia Gelatinosa / physiology*

Substances

  • Quinoxalines
  • Receptors, AMPA
  • Receptors, Amino Acid
  • Receptors, Glutamate
  • Receptors, Kainic Acid
  • Receptors, N-Methyl-D-Aspartate
  • 6-Cyano-7-nitroquinoxaline-2,3-dione
  • 2-Amino-5-phosphonovalerate