Article date: 1992/10/1
PubMed ID: 1359375
Journal name: Brain research. Molecular brain research (ISSN: 0169-328X)
We have characterized a high affinity site of the alpha-amino-3 hydroxy-5-methyl-isoxazole-4-propionate (AMPA) receptor in in vitro living slices of adult rat neocortex using [3H]CNQX, and AMPA antagonist. [3H]CNQX labelled multiple binding sites with a Bmax of a high affinity site of approximately 470 fmol/mg protein and an apparent Kd of 11.3 nM. The high affinity site of the AMPA receptor could be down-regulated (36%) by 2 h preincubations in quisqualate, an AMPA agonist. Increases in electrical activity induced by a combination of veratridine and glutamate also led to an average decrease of the high affinity AMPA receptor number of 17%. In addition, preincubations with muscimol, a GABAA agonist, as well as glutamate agonists kainate and N-methyl-D-aspartate (NMDA) led to an average increase in high affinity AMPA receptor number of 17%, 14%, and 37%, respectively. The present results show that a ligand-gated high affinity AMPA receptor can be regulated by agonist stimulation as well as changes in neural activity.
Author List: Lanius R A, Shaw C
Publication Types: Journal Article; Research Support, Non-U.S. Gov't
Substances mentioned in the article: Oxadiazoles; Quinoxalines; Receptors, AMPA; Receptors, Neurotransmitter; Tritium; Muscimol; N-Methylaspartate; 6-Cyano-7-nitroquinoxaline-2,3-dione; Quisqualic Acid; Kainic Acid;
Mesh terms: 6-Cyano-7-nitroquinoxaline-2,3-dione; Animals; Cerebral Cortex/metabolism; In Vitro Techniques; Kainic Acid/metabolism; Male; Muscimol/metabolism; N-Methylaspartate/metabolism; Oxadiazoles; Quinoxalines/metabolism; Quisqualic Acid/metabolism; Radioligand Assay; Rats; Rats, Sprague-Dawley; Receptors, AMPA; Receptors, Neurotransmitter/metabolism; Tritium;