• A transmembrane pore that presents a hydrophilic channel for ions to cross a lipid bilayer down their electrochemical gradients. Some degree of ion specificity is usually observed and typically a million ions per second may flow. Channels may be permanently open, like the potassium leak channel or they may be voltage gated, like the sodium channel or ligand gated like the acetylcholine receptor.
  NCI Thesaurus
  U.S. National Cancer Institute, 2021
• Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.
  NLM Medical Subject Headings
  U.S. National Library of Medicine, 2021
• (membrane channel) Molecule-sized pores in biomembranes that permit the passage of hydrophilic solutes such as inorganic ions, and the proteins that form such pores and control their permeability.
  CRISP Thesaurus
  National Institutes of Health, 2006
• Ion channel, protein expressed by virtually all living cells that creates a pathway for charged ions from dissolved salts, including sodium, potassium, calcium, and chloride ions, to pass through the otherwise impermeant lipid cell membrane. Operation of cells in the nervous system, contraction of...
  Encyclopedia Britannica
  Encyclopedia Britannica, Inc., 2020