Referenced in: none

Automatically associated channels: Kir2.1 , Kir2.2 , Kir2.3 , Kir4.1

Title: AMPA receptor-mediated modulation of inward rectifier K+ channels in astrocytes of mouse hippocampus.

Authors: Wolfgang Schröder, Gerald Seifert, Kerstin Hüttmann, Stefan Hinterkeuser, Christian Steinhäuser

Journal, date & volume: Mol. Cell. Neurosci., 2002 Mar , 19, 447-58

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/11906215

Abstract
Astrocytes and neurons are tightly associated and recent data suggest a direct signaling between neuronal and glial cells in vivo. To further analyze these interactions, the patch-clamp technique was combined with single-cell RT-PCR in acute hippocampal brain slices. Subsequent to functional analysis, the cytoplasm of the same cell was harvested to perform transcript analysis and identify subunits that underlie inwardly rectifying K+ currents (I(Kir)) in astrocytes of the CA1 stratum radiatum. Transcripts encoding Kir2.1, Kir2.2, or Kir2.3, were encountered in a majority of cells, while Kir4.1 was less frequent. Further investigation revealed that glial Kir channels are rapidly inhibited upon activation of AMPA-type glutamate receptors, most probably due a receptor-mediated influx of Na+, which plugs the channels from the intracellular side. A transient inhibition of I(Kir) in astrocytes in response to neuronal glutamate release and glial AMPA receptor activation represents a further, so far undetected mechanism to balance neuronal excitability.