The impact of the glial spatial buffering on the K(+) Nernst potential
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Updated: May 19, 2026

Double-barreled and Concentric Microelectrodes for Measurement of Extracellular Ion Signals in Brain Tissue
Published on: September 5, 2015
1Interdisciplinary Center for Scientific Computing, University of Heidelberg, Im Neuenheimer Feld 294, 69120 Heidelberg, Germany.
Abstract:
Astrocytes play a critical role in CNS metabolism, regulation of volume and ion homeostasis of the interstitial space. Of special relevance is their clearance of K(+) that is released by active neurons into the extracellular space. Mathematical analysis of a modified Nernst equation for the electrochemical equilibrium of neuronal plasma membranes, suggests that K(+) uptake by glial cells is not only relevant during neuronal activity but also has a non-neglectable impact on the basic electrical membrane properties, specifically the resting membrane potential, of neurons and might be clinically valuable as a factor in the genetics and epigenetics of the epilepsy and tuberous sclerosis complex.
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