[Computation of the K+, Na+ and Cl- fluxes through plasma membrane of animal cell with Na+/K+ pump, NKCC, NC cotransporters, and ionic channels with and without non-Goldman rectification in K+ channels. Norma and apoptosis].
The balance of K+, Na+ and Cl- fluxes through cell membrane with the Na+/K+ pump, ion channels and NKCC and NC cotransporters is considered. It is shown that all unidirectional K+, Na+ and Cl- fluxes through cell membrane, permeability coefficients of ion channels and membrane potential can be computed for balanced ion distribution between cell and the medium if K+, Na+ and Cl- concentration in cell water and three fluxes are known: total Cl- flux, total K+ influx and ouabain-inhibitable "pump" component of the K+ influx. Changes in the mortovalent ion balance in lymphoid cells U937 induced to apoptosis by 1 microM staurosporine are analyzed as an example. It is found that the apoptotic shift in ion and water balance in studied cells is caused by a decrease in the pump activity which is accompanied by a decrease in the integral permeability of Na+ channels without significant increase in K+ and Cl- channel permeabilities. Computation shows that only a small part of the total fluxes of K+, Na+ and Cl- accounts for the fluxes via NKCC and NC cotransporters. Therefore, cotransport fluxes can not be studied using inhibitors.
Rubashkin
A A
AA
Iurinskaia
V E
VE
Vereninov
A A
AA
D017209:Apoptosis; D002462:Cell Membrane / Q000378:metabolism*; D002713:Chlorine / Q000378:metabolism*; D006801:Humans; D017136:Ion Transport; D007477:Ions / Q000378:metabolism; D056004:Molecular Dynamics Simulation; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D028021:Sodium-Potassium-Chloride Symporters / Q000378:metabolism; D019311:Staurosporine / Q000494:pharmacology; D020298:U937 Cells; D014882:Water-Electrolyte Balance
D007477:Ions; D028021:Sodium-Potassium-Chloride Symporters; D002713:Chlorine; D010042:Ouabain; D012964:Sodium; D019311:Staurosporine; D011188:Potassium