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Electrical coupling among Bergmann glial cells and its modulation by glutamate receptor activation
Author(s) -
Müller Thomas,
Möller Thomas,
Neuhaus Jochen,
Kettenmann Helmut
Publication year - 1996
Publication title -
glia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.954
H-Index - 164
eISSN - 1098-1136
pISSN - 0894-1491
DOI - 10.1002/(sici)1098-1136(199608)17:4<274::aid-glia2>3.0.co;2-#
Subject(s) - gap junction , biology , lucifer yellow , kainate receptor , cell junction , biophysics , ampa receptor , coupling (piping) , glutamate receptor , microbiology and biotechnology , neuroscience , receptor , intracellular , cell , materials science , biochemistry , metallurgy
Abstract We studied the characteristics of electrical coupling between Bergmann glial cells in mouse cerebellar slices using Lucifer Yellow injection, patch‐clamping cell pairs, and ultrastructural inspection. While early postnatal cells (days 5–7) were not coupled, coupling was abundant at postnatal days 20–24. Coupled cells were arranged perpendicular to the parallel fibers in a parasagittal section, forming a string, rather than a cluster of cells. Electron microscopy revealed that gap junctions were abundant in the distal parts of the processes. Gap junctions between cell bodies and processes were very rare, and no gap junctions were found between cell bodies of adjacent Bergmann glial cells. The junctional conductance was voltage and time independent and could be markedly reduced by halothane. Alkalization of cells (by applying NH 4 + increased the junctional conductance to 150%, while acidification of the cell interior (by removing NH 4 + ) led to a decrease to 70%. Activation of AMPA receptors induced a blockade of the junctional conductance to 30% of the control. This link is most likely mediated by the influx of Ca 2+ via the receptor since this effect was not observed in Ca 2+ ‐free medium, suggesting that Ca 2+ entry via the kainate receptor pore led to the closure of gap junctions. These studies indicate that electrical coupling between Bergmann glial cells is not only developmentally regulated but also controlled by physiological stimuli. © 1996 Wiley‐Liss, Inc.