ion channel


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i·on chan·nel

a specific macromolecular protein pathway, with an aqueous "pore," which traverses the lipid bilayer of a cell's plasma membrane and maintains or modulates the electrical potential across this barrier by allowing the controlled influx or exit of small inorganic ions such as Na+, K+, Cl-, and Ca2+. It plays an important role in propagation of the action potential in neurons, but also may control transduction of extracellular signals and contraction in muscle cells. In general, ion channels are characterized by their selectivity for certain ions, their specific regulation or gating of these ions, and their specific sensitivity to toxins.

ion channel

n.
A pathway through a protein molecule or complex in a cell membrane that modulates the electrical potential across the membrane by controlling the passage of small inorganic ions into and out of the cell.

ion channel

A protein that spans the lipid bilayer of the cell membrane and regulates the movement of charged particles (e.g., electrolytes) into and out of cells.
See also: channel
References in periodicals archive ?
Figure S2: comparison of ion channel currents in cells after different differentiation times.
where [g.sub.Na.sup.max]=120mS[cm.sup.-2] and [g.sub.K.sup.max]=36mS[cm.sup.-2] is the maximal conductance of the corresponding ion channel. [[chi].sub.i] i=(Na, K) is a scaling factor, which equals to the ratio of active (non-blocked) i-type ion channel numbers to total itype ion channel number within a given membrane size [30, 31].
In this part, a numerical calculation is used to analyze the effects of the inner and outer radii on the dispersion curves of the azimuthally symmetric (l = 0) ES and TM modes and the interaction between them under different EM characteristics of the ion channel. For the convenience of the numerical calculation, The dispersion frequency [omega] and the wavenumber [k.sub.z] are normalized by the beam frequency [[omega].sub.b] and the speed of the light in vacuum; that is, [mathematical expression not reproducible].
Stockand, "Restrictive expression of acid-sensing ion channel 5 (Asic5) in unipolar brush cells of the vestibulocerebellum," PLoS One, vol.
The prediction for ion channel types of the conotoxins requires that the protein sequences are represented by the eigenvectors of the same number of dimension.
There is a huge diversity of ion channels in both the outer and inner mitochondrial membrane (OMM, IMM).
Dr Charles Large, chief executive officer for Autifony, said: "Novel and more effective treatments for schizophrenia are desperately needed and the ion channels that we are targeting are closely implicated in brain circuits which are believed to be dysfunctional in schizophrenia.
By combining the microfluidic Cytocentering technology with a sophisticated liquid handling system and an all new digital amplifier with both voltage- and current clamp capabilities, the CytoPatch2 can record whole cell and single channel currents, and works equally well for voltage gated ion channels (constant perfusion mode) and ligand gated ion channels (fast solution exchange, <4ms compound wash-in, <10ms wash-out).
longibrachiatum was linked to increased permeability, via voltage-dependent sodium and potassium ion channels, in some sperm cellular membranes.
The disease, which can cause arrhythmias that lead to seizures and sudden death, is caused by a mutation in any of various genes encoding cardiac ion channels or their associated proteins.
Since the CFTR gene discovery, hundreds of mutations have been identified, including G551D, which results in a protein that disrupts the ion channel function of the cystic fibrosis protein.