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Biophys J
1996 Aug 01;712:682-94. doi: 10.1016/S0006-3495(96)79268-8.
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[K+] dependence of open-channel conductance in cloned inward rectifier potassium channels (IRK1, Kir2.1).
Lopatin AN, Nichols CG.
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Potassium conduction through unblocked inwardly rectifying (IRK1, Kir2.1) potassium channels was measured in inside-out-patches from Xenopus oocytes, after removal of polyamine-induced strong inward rectification. Unblocked IRK1 channel current-voltage (I-V) relations show very mild inward rectification in symmetrical solutions, are linearized in nonsymmetrical solutions that bring the K+ reversal potential to extreme negative values, and follow Goldman-Hodgkin-Katz constant field equation at extreme positive E alpha. When intracellular K+ concentration (KIN) was varied, at constant extracellular K+ concentration (KOUT) the conductance at the reversal potential (GREV) followed closely the predictions of the Goldman-Hodgkin-Katz constant field equation at low concentrations and saturated sharply at concentrations of > 150 mM. Similarly, when KOUT was varied, at constant KIN, GREV saturated at concentrations of > 150 mM. A square-root dependence of conductance on KOUT is a well-known property of inward rectifier potassium channels and is a property of the open channel. A nonsymmetrical two-site three-barrier model can qualitatively explain both the I-V relations and the [K+] dependence of conductance of open IRK1 (Kir2.1) channels.
Alvarez,
Calculation of ion currents from energy profiles and energy profiles from ion currents in multibarrier, multisite, multioccupancy channel model.
1992, Pubmed
Alvarez,
Calculation of ion currents from energy profiles and energy profiles from ion currents in multibarrier, multisite, multioccupancy channel model.
1992,
Pubmed Armstrong,
Inactivation of the potassium conductance and related phenomena caused by quaternary ammonium ion injection in squid axons.
1969,
Pubmed Blatz,
Ion conductance and selectivity of single calcium-activated potassium channels in cultured rat muscle.
1984,
Pubmed Cecchi,
Characterization of a calcium-activated potassium channel from rabbit intestinal smooth muscle incorporated into planar bilayers.
1986,
Pubmed Chang,
Ion permeation properties of the glutamate receptor channel in cultured embryonic Drosophila myotubes.
1994,
Pubmed Chizmadjev,
Ion transport across sodium channels in biological membranes.
1977,
Pubmed Ciani,
A model for anomalous rectification: electrochemical-potential-dependent gating of membrane channels.
1978,
Pubmed Cohen,
Internal and external K+ help gate the inward rectifier.
1989,
Pubmed Coronado,
Ionic selectivity, saturation, and block in a K+-selective channel from sarcoplasmic reticulum.
1980,
Pubmed Fakler,
Strong voltage-dependent inward rectification of inward rectifier K+ channels is caused by intracellular spermine.
1995,
Pubmed
,
Xenbase Fakler,
A structural determinant of differential sensitivity of cloned inward rectifier K+ channels to intracellular spermine.
1994,
Pubmed
,
Xenbase Ficker,
Spermine and spermidine as gating molecules for inward rectifier K+ channels.
1994,
Pubmed
,
Xenbase Finkelstein,
The gramicidin A channel: a review of its permeability characteristics with special reference to the single-file aspect of transport.
1981,
Pubmed French,
Ion permeation, divalent ion block, and chemical modification of single sodium channels. Description by single- and double-occupancy rate-theory models.
1994,
Pubmed Goldman,
POTENTIAL, IMPEDANCE, AND RECTIFICATION IN MEMBRANES.
1943,
Pubmed Hagiwara,
Effects of internal potassium and sodium on the anomalous rectification of the starfish egg as examined by internal perfusion.
1979,
Pubmed Hagiwara,
The anomalous rectification and cation selectivity of the membrane of a starfish egg cell.
1974,
Pubmed Hill,
Potassium channel of cardiac sarcoplasmic reticulum is a multi-ion channel.
1989,
Pubmed Hill,
Cooperative effects in models of steady-state transport across membranes. IV. One-site, two-site, and multisite models.
1971,
Pubmed Hille,
Potassium channels as multi-ion single-file pores.
1978,
Pubmed Hille,
Ionic selectivity, saturation, and block in sodium channels. A four-barrier model.
1975,
Pubmed Ho,
Cloning and expression of an inwardly rectifying ATP-regulated potassium channel.
1993,
Pubmed
,
Xenbase HODGKIN,
The potassium permeability of a giant nerve fibre.
1955,
Pubmed Kubo,
Primary structure and functional expression of a rat G-protein-coupled muscarinic potassium channel.
1993,
Pubmed
,
Xenbase Kubo,
Primary structure and functional expression of a mouse inward rectifier potassium channel.
1993,
Pubmed
,
Xenbase Lopatin,
Potassium channel block by cytoplasmic polyamines as the mechanism of intrinsic rectification.
1994,
Pubmed
,
Xenbase Lopatin,
The mechanism of inward rectification of potassium channels: "long-pore plugging" by cytoplasmic polyamines.
1995,
Pubmed
,
Xenbase Lu,
A conductance maximum observed in an inward-rectifier potassium channel.
1994,
Pubmed
,
Xenbase Lu,
Electrostatic tuning of Mg2+ affinity in an inward-rectifier K+ channel.
1994,
Pubmed
,
Xenbase Makhina,
Cloning and expression of a novel human brain inward rectifier potassium channel.
1994,
Pubmed
,
Xenbase Matsuda,
Ohmic conductance through the inwardly rectifying K channel and blocking by internal Mg2+.
,
Pubmed Neyton,
Potassium blocks barium permeation through a calcium-activated potassium channel.
1988,
Pubmed Nichols,
The 'inner core' of inwardly rectifying K+ channels.
1993,
Pubmed Périer,
Primary structure and characterization of a small-conductance inwardly rectifying potassium channel from human hippocampus.
1994,
Pubmed
,
Xenbase Sakmann,
Conductance properties of single inwardly rectifying potassium channels in ventricular cells from guinea-pig heart.
1984,
Pubmed Schumaker,
A simple model for multi-ion permeation. Single-vacancy conduction in a simple pore model.
1990,
Pubmed Shapiro,
Selectivity and gating of the type L potassium channel in mouse lymphocytes.
1991,
Pubmed Tang,
Perfusing patch pipettes.
1992,
Pubmed Vandenberg,
Inward rectification of a potassium channel in cardiac ventricular cells depends on internal magnesium ions.
1987,
Pubmed Wagoner,
Cation permeation through the voltage-dependent potassium channel in the squid axon. Characteristics and mechanisms.
1987,
Pubmed Yang,
Control of rectification and permeation by residues in two distinct domains in an inward rectifier K+ channel.
1995,
Pubmed
,
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