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Acid-Sensing Ion Channels (ASICs) and pH in Synapse Physiology

  • John A. Wemmie
  • Xiang-ming Zha
  • Michael J. Welsh

Abstract

Although brain pH is tightly controlled, it can be more dynamic than commonly appreciated. Physiological fluctuations in extracellular pH provide ample opportunity for protons to influence synaptic signaling. A number of synaptic proteins are modified by extracellular pH. Of these, the acid sensing ion channels (ASICs) are gated by extracellular protons and thus they may be particularly well suited to respond to synaptic pH. Here we review extracellular pH changes that accompany neural activity, the synaptic localization of ASICs, and their known effects on synapse function. Results from manipulating ASICs in mice suggest important roles for synaptic ASICs in behavior and neurological disease.

Keywords

NMDA Receptor Dendritic Spine Cortical Spreading Depression Extracellular Proton Delay Eyeblink Conditioning 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • John A. Wemmie
    • 1
  • Xiang-ming Zha
    • 2
  • Michael J. Welsh
    • 3
  1. 1.Department of Psychiatry Neuroscience Program and Department of Veterans Affairs Medical CenterIowa CityIA
  2. 2.Department of Internal Medicine and Howard Hughes Medical InstituteIowa CityUSA
  3. 3.Departments of Internal Medicine and Molecular Physiology and Howard Hughes Medical InstituteIowa CityUSA

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