Regional variations in the pharmacology of AMPA receptors as revealed by receptor autoradiography

Brain Res. 1994 Nov 21;664(1-2):202-6. doi: 10.1016/0006-8993(94)91971-2.

Abstract

Using quantitative autoradiography, we examined the ability of NBQX (2,3-dihydro-6-nitro-7-sulfamoyl-benzo(f)-quinoxaline), S-AMPA (alpha-amino-3-hydroxy-5-methylisoxazole propionic acid), L-glutamate and NS-257 (1,2,3,6,7,8-hexahydro-3-(hydroxyimino)- N,N,7-trimethyl-2-oxobenzo[2,1-b:3,4-c']dipyrrole-5-sulfonam ide) to compete for [3H]AMPA binding sites in several forebrain regions and cerebellar cortex. NBQX had a higher affinity (P < 0.0001) in cerebellar molecular layer than in any forebrain region, whereas the opposite was true for AMPA (P < 0.001). L-Glutamate and NS-257 had different regional patterns of displacement. Consequently, cerebellum and forebrain have distinct rank orders of potency for AMPA receptor ligands. These results suggest that there are regional variations in the pharmacological specificity of AMPA receptors.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Autoradiography
  • Binding, Competitive
  • Brain / drug effects*
  • Brain / metabolism
  • Cerebellar Cortex / drug effects
  • Glutamic Acid / pharmacology*
  • Indoles / pharmacology*
  • Male
  • Molecular Structure
  • Prosencephalon / drug effects
  • Quinoxalines / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, AMPA / antagonists & inhibitors
  • Receptors, AMPA / drug effects*
  • Sulfonamides / pharmacology*
  • alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / pharmacology*

Substances

  • Indoles
  • NS 257
  • Quinoxalines
  • Receptors, AMPA
  • Sulfonamides
  • 2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline
  • Glutamic Acid
  • alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid