Article date: 1990/12/1
PubMed ID: 1979144
Journal name: Molecular pharmacology (ISSN: 0026-895X)
The GluR1 cDNA clone encodes a functional excitatory amino acid receptor (Hollmann et al., Nature 342: 643-648 (1989]. We have studied the pharmacological properties of this homomeric (single subunit) receptor expressed in Xenopus oocytes and compared these properties with those of receptors encoded by rat forebrain mRNA. (RS)-alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionate, quisqualate, and glutamate were partial agonists at both GluR1 and forebrain non-N-methyl-D-aspartate (-NMDA) receptors. The potency of the agonists kainate, domoate, and glutamate was higher, and that of the antagonists 6-cyano-7-nitro-quinoxalinedione and 6,7-dichloro-3-hydroxy-2-quinoxaline carboxylic acid lower, for GluR1 receptors as compared with forebrain non-NMDA receptors. The GluR1 receptor differed strikingly from forebrain-derived non-NMDA receptors, however, in that it exhibited slow, calcium-dependent desensitization. Thus, most properties of the GluR1 receptor are similar but not identical to those of non-NMDA receptors expressed from forebrain mRNA. These results indicate that the ligand recognition sites on GluR1 homomeric receptors are subtly different from those of non-NMDA receptors expressed from a mixture of forebrain mRNA.
Author List: Dawson T L, Nicholas R A, Dingledine R
Publication Types: Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.
Substances mentioned in the article: Chloride Channels; Membrane Proteins; Quinoxalines; Receptors, Glutamate; Receptors, Neurotransmitter; Ibotenic Acid; 6-Cyano-7-nitroquinoxaline-2,3-dione; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; Quisqualic Acid; Kainic Acid;
Mesh terms: 6-Cyano-7-nitroquinoxaline-2,3-dione; Animals; Chloride Channels; Ganglia, Spinal/chemistry; Hippocampus/chemistry; Ibotenic Acid/analogs & derivatives; Kainic Acid/pharmacology; Membrane Proteins/drug effects; Oocytes/chemistry; Quinoxalines/pharmacology; Quisqualic Acid/pharmacology; Receptors, Glutamate; Receptors, Neurotransmitter/analysis; Xenopus; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid;