Excitatory Amino Acid Receptors Appear to Mediate Paroxysmal Depolarizing Shifts in Rat Neocortical Neurons in Vitro

Brain Res. 1992 Apr 10;577(1):151-4. doi: 10.1016/0006-8993(92)90549-o.

Abstract

This study was designed to assess some of the contributions of excitatory amino acids to locally evoked responses in neurons in slices from frontal motor cortex in Sprague-Dawley rats. Intracellular recordings were obtained from 54 cortical neurons. Paroxysmal depolarization shifts (PDS) were evoked by local single pulse stimulation in cortex or in a small number of cases (n = 2) occurred spontaneously. These potentials could be abolished by application of kynurenic acid, a broad spectrum excitatory amino acid receptor antagonist. They were enhanced in Mg(2+)-free medium and could then be antagonized by application of D,L-2-amino-5-phosphonovalerate (AP5), a selective blocker of the N-methyl-D-aspartate (NMDA) receptors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 2-Amino-5-phosphonovalerate / pharmacology
  • Amino Acids*
  • Animals
  • Frontal Lobe / cytology
  • Frontal Lobe / drug effects
  • Frontal Lobe / physiology*
  • In Vitro Techniques
  • Kynurenic Acid
  • Magnesium / physiology
  • Membrane Potentials / drug effects
  • Membrane Potentials / physiology
  • Motor Cortex / cytology
  • Motor Cortex / drug effects
  • Motor Cortex / physiology*
  • Neurons / drug effects
  • Neurons / physiology*
  • Rats
  • Rats, Inbred Strains
  • Receptors, Amino Acid
  • Receptors, Cell Surface / physiology*
  • Receptors, N-Methyl-D-Aspartate / antagonists & inhibitors

Substances

  • Amino Acids
  • Receptors, Amino Acid
  • Receptors, Cell Surface
  • Receptors, N-Methyl-D-Aspartate
  • 2-Amino-5-phosphonovalerate
  • Kynurenic Acid
  • Magnesium