Evidence that the parafascicular projection to the subthalamic nucleus is glutamatergic

Neuroreport. 1993 Jun;4(6):613-5. doi: 10.1097/00001756-199306000-00002.

Abstract

The parafascicular nucleus projection to the subthalamic neurones has an excitatory synaptic effect. We have examined the possible glutamatergic mediation of this pathway. The initial excitatory response elicited by electrical stimulation of the parafascicular neurones was inhibited by a microinjection of excitatory amino acid receptor antagonists into the subthalamic nucleus. The antagonists were the broad spectrum kynurenic acid, the NMDA selective antagonist d-AP-5 and the AMPA antagonist CNQX. Their effects were dose-dependent and reversible. The results suggest that the excitatory effect of the parafascicular neurones is mediated by AMPA and NMDA receptors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 2-Amino-5-phosphonovalerate / pharmacology
  • 6-Cyano-7-nitroquinoxaline-2,3-dione
  • Anesthesia
  • Animals
  • Electric Stimulation
  • Glutamates / physiology*
  • Histocytochemistry
  • Kynurenic Acid / pharmacology
  • Male
  • Neural Pathways / cytology
  • Neural Pathways / drug effects
  • Neural Pathways / physiology
  • Quinoxalines / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, AMPA
  • Receptors, Amino Acid / drug effects
  • Receptors, Glutamate / drug effects
  • Receptors, N-Methyl-D-Aspartate / drug effects
  • Synaptic Transmission / drug effects
  • Thalamic Nuclei / physiology*

Substances

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