title: [Role of image force in a water pore of K+ channel in the channel permeability--nonlocal electrostatic effects].
abstract: A modified Parsegian formula for the calculation of the mage force in a water pore, which takes into account nonlocal electrostatic effects, has been applied to the analysis of changes in the permeability of K+ channels. It has been shown that the channel permeability increases 3 x 10(3) times as the width of the pore increases from 4 to 10 angstroms when the energy is calculated by the modified Parsegian formula and only 16 times if the classical Parsegian formula is used. We conclude that the image force in a water pore within K+ channels plays an important part in the change of channel permeability. Accounting for nonlocal electrostatic effects indicates that the permeability of the K+ channel is more strongly related to the size of the water pore than previously assumed by the original Parsegian formula.
authors: A A
authors: AA
authors: Rubashkin
authors: P
authors: P
authors: Iserovich
mesh_terms: D015640:Ion Channel Gating; D010539:Permeability; D024642:Potassium Channels, Voltage-Gated / Q000502:physiology*; D055672:Static Electricity; D014867:Water / Q000502:physiology*
chemical_list: D024642:Potassium Channels, Voltage-Gated; D014867:Water