Calcium-permeable AMPA-kainate receptors in fusiform cerebellar glial cells. Journal Article

Author(s): Burnashev, Nail A; Khodorova, Alla; Jonas, Peter; Helm, P. J.; Wisden, William; Monyer, Hannah; Seeburg, Peter H; Sakmann, Bert
Article Title: Calcium-permeable AMPA-kainate receptors in fusiform cerebellar glial cells.
Abstract: Glutamate-operated ion channels (GluR channels) of the L-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-kainate subtype are found in both neurons and glial cells of the central nervous system. These channels are assembled from the GluR-A, -B, -C, and -D subunits; channels containing a GluR-B subunit show an outwardly rectifying current-voltage relation and low calcium permeability, whereas channels lacking the GluR-B subunit are characterized by a doubly rectifying current-voltage relation and high calcium permeability. Most cell types in the central nervous system coexpress several subunits, including GluR-B. However, Bergmann glia in rat cerebellum do not express GluR-B subunit genes. In a subset of cultured cerebellar glial cells, likely derived from Bergmann glial cells. GluR channels exhibit doubly rectifying current-voltage relations and high calcium permeability, whereas GluR channels of cerebellar neurons have low calcium permeability. Thus, differential expression of the GluR-B subunit gene in neurons and glia is one mechanism by which functional properties of native GluR channels are regulated.
Keywords: Animals; Rats; Cells, Cultured; Gene Expression; Calcium; Calcium/metabolism; Ion Channel Gating; RNA, Messenger; Cell Membrane Permeability; Glutamates; Receptors, Neurotransmitter; Receptors, Kainic Acid; RNA, Messenger/genetics; Cerebellum/physiology; Glutamates/physiology; Neuroglia/physiology; Nucleic Acid Hybridization; Receptors, Neurotransmitter/physiology
Journal Title: Science
Volume: 256
Issue 5063
ISSN: 0036-8075
Publisher: American Association for the Advancement of Science  
Date Published: 1992-06-12
Start Page: 1566
End Page: 1570
DOI: 10.1126/science.1317970
Open access: no