Excitatory amino acid receptors in glial progenitor cells: molecular and functional properties.
We have analyzed the molecular and biophysical properties of glutamate-gated channels in cells of the oligodendrocyte lineage, using both the CG-4 primary cell line (Louis et al: J. Neurosci. Res. 31:193-204, 1992a) and oligodendrocyte progenitors purified from the rat cerebral cortex. CG-4 progenitor cells, as well as primary progenitors, were stained with a specific anti-GABA antibody. In whole-cell patch-clamp recordings, rapid perfusion of the agonists L-glutamate, kainate, and AMPA produced rapidly desensitizing currents in CG-4 cells. NMDA was ineffective. Both rapidly desensitizing and steady-state components of responses to kainate were inhibited by the kainate/AMPA receptor antagonist CNQX. Northern blot analysis of total mRNA isolated from CG-4 cells revealed co-expression of both AMPA- and kainate-preferring glutamate receptor subunits. The activation of glutamate receptors in CG-4 cells caused a rapid and transient elevation of mRNAs for the immediate early gene NGFI-A.
Gallo
V
V
Laboratory of Cellular and Molecular Neurophysiology, National Institute of Child Health and Human Development, NIH, Bethesda, Maryland 20892.
Patneau
D K
DK
Mayer
M L
ML
Vaccarino
F M
FM
D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D004268:DNA-Binding Proteins / Q000096:biosynthesis; D051766:Early Growth Response Protein 1; D005786:Gene Expression Regulation / Q000187:drug effects; D017781:Genes, Immediate-Early / Q000187:drug effects; D018698:Glutamic Acid / Q000494:pharmacology*; D017874:Immediate-Early Proteins; D007608:Kainic Acid / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects; D016202:N-Methylaspartate / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000502:physiology*; D009498:Neurotoxins / Q000494:pharmacology*; D009836:Oligodendroglia / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017470:Receptors, Glutamate / Q000187:drug effects / Q000502:physiology*; D013234:Stem Cells / Q000187:drug effects / Q000502:physiology*; D014157:Transcription Factors / Q000096:biosynthesis
D004268:DNA-Binding Proteins; D051766:Early Growth Response Protein 1; C486110:Egr1 protein, rat; D017874:Immediate-Early Proteins; D009419:Nerve Tissue Proteins; D009498:Neurotoxins; D017470:Receptors, Glutamate; D014157:Transcription Factors; D018698:Glutamic Acid; D016202:N-Methylaspartate; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D007608:Kainic Acid