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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Notes
A constant of proportionality that relates the electric field in a material to the electric displacement in that material. It characterizes the tendency of the atomic charge in an insulating material to distort in the presence of an electric field.
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Acknowledgments
The author is very grateful to Prof. Christine R. Rose (Institute for Neurobiology, Heinrich-Heine-University Duesseldorf) for her inspiring advices on neurobiological aspects of the potassium spatial buffering. The work was supported by the Bundesministerium für Bildung and Forschung (NGFNPlus; FKZ: 01GS08152).
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Noori, H.R. The impact of the glial spatial buffering on the K+ Nernst potential. Cogn Neurodyn 5, 285–291 (2011). https://doi.org/10.1007/s11571-011-9165-x
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DOI: https://doi.org/10.1007/s11571-011-9165-x