Modulatory effects of acid-sensing ion channels on action potential generation in hippocampal neurons.

Details

Serval ID
serval:BIB_D92E31799070
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Modulatory effects of acid-sensing ion channels on action potential generation in hippocampal neurons.
Journal
American Journal of Physiology. Cell Physiology
Author(s)
Vukicevic M., Kellenberger S.
ISSN
0363-6143[print], 0363-6143[linking]
Publication state
Published
Issued date
2004
Volume
287
Number
3
Pages
C682-C690
Language
english
Abstract
Extracellular acidification has been shown to generate action potentials (APs) in several types of neurons. In this study, we investigated the role of acid-sensing ion channels (ASICs) in acid-induced AP generation in brain neurons. ASICs are neuronal Na(+) channels that belong to the epithelial Na(+) channel/degenerin family and are transiently activated by a rapid drop in extracellular pH. We compared the pharmacological and biophysical properties of acid-induced AP generation with those of ASIC currents in cultured hippocampal neurons. Our results show that acid-induced AP generation in these neurons is essentially due to ASIC activation. We demonstrate for the first time that the probability of inducing APs correlates with current entry through ASICs. We also show that ASIC activation in combination with other excitatory stimuli can either facilitate AP generation or inhibit AP bursts, depending on the conditions. ASIC-mediated generation and modulation of APs can be induced by extracellular pH changes from 7.4 to slightly <7. Such local extracellular pH values may be reached by pH fluctuations due to normal neuronal activity. Furthermore, in the plasma membrane, ASICs are localized in close proximity to voltage-gated Na(+) and K(+) channels, providing the conditions necessary for the transduction of local pH changes into electrical signals.
Keywords
Acids, Action Potentials/physiology, Animals, Cells, Cultured, Electrophysiology, Embryo, Mammalian, Extracellular Fluid/chemistry, Hippocampus/physiology, Hydrogen-Ion Concentration, Ion Channels/physiology, Mice, Neurons/physiology, Patch-Clamp Techniques, Recombinant Proteins/metabolism, Transfection
Pubmed
Web of science
Create date
24/01/2008 12:45
Last modification date
20/08/2019 15:58
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