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Ion Channels

  1. Olaf S. Andersen1,
  2. Helgi I. Ingólfsson1,2,
  3. Jens A. Lundbæk1,2

Published Online: 15 AUG 2009

DOI: 10.1002/3527600434.eap673

Encyclopedia of Applied Physics

Encyclopedia of Applied Physics

How to Cite

Andersen, O. S., Ingólfsson, H. I. and Lundbæk, J. A. 2009. Ion Channels. Encyclopedia of Applied Physics. .

Author Information

  1. 1

    Weill Cornell Medical College New York, Department of Physiology and Biophysics, New York, USA

  2. 2

    Danish Technical University, Quantum Protein Centre, Physics Department, Lyngby, Denmark

Publication History

  1. Published Online: 15 AUG 2009


Ion channels catalyze the transmembrane movement of small inorganic ions across biological membranes. They do so by forming continuous, hydrophilic pores through which ions can cross the barrier imposed by the lipid bilayer hydrophobic core. Ion channels serve many functions: they underlie the changes in membrane potential that control many cell functions, including the propagated electrical signaling (the action potentials) in electrically excitable cells; they allow for the bulk movement of ions across cell membranes. In this chapter, we summarize key features of ion channels, with special emphasis on the channels in the plasma membrane — their structure and catalytic power, the generation of membrane potential changes, the regulation (or gating) that underlies normal channel function, and how channel function can be modulated by small molecules.


  • bilayer-spanning;
  • transmembrane;
  • ion selectivity;
  • channelopathies;
  • epithelial sodium channel