Astroglial gap junctions and potassium buffering

Astrocytes form networks in which individual astrocytes are coupled to their neighbors via gap junctions. These networks are thought to help buffering rises of extracellular potassium and thereby to control neuronal excitability. Björn Breithausen, a PhD student in our lab, and colleagues have tested if acute pharmacological blockade of gap junctions impairs potassium buffering. In contrast to our expectations, we found that blockade of gap junctions only affected very local and very large extracellular potassium increases, which are usually only found in brain diseases. The study was published in GLIA.

Breithausen B, Kautzmann S, Boehlen A, Steinhäuser C, Henneberger C (2020) Limited contribution of astroglial gap junction coupling to buffering of extracellular K+ in CA1 stratum radiatum. Glia. 68(5):918-931 (link, open access)