Cellular inhomogeneity in dog red cells as revealed by sodium flux.
Unidirectional (24)Na fluxes across the dog red blood cell membrane were measured. The kinetics were incompatible with a single time constant but could be accounted for in terms of a two-series compartment cell model, with approximately 1% of cell Na in the outer compartment. Dog red blood cells are known to be inhomogeneous in their Na and K permeabilities. Theoretical analysis showed that such cellular inhomogeneity in the Na permeability coefficient might in principle account for the flux data. In order to evaluate the inhomogeneity effect, a technique based on the differential response of cells suspended in isosmolar high K buffers was devised to measure the variations in Na permeability in the cell population. A variation in the Na permeability coefficient of approximately 30% was found. This inhomogeneity is insufficient to account for the flux data.
D000818:Animals; D001692:Biological Transport; D001810:Blood Volume; D002021:Buffers; D002463:Cell Membrane Permeability; D002859:Chromium Isotopes; D003202:Computers, Analog; D004285:Dogs / Q000502:physiology*; D004912:Erythrocytes / Q000378:metabolism*; D005260:Female; D007552:Isotonic Solutions; D007700:Kinetics; D008297:Male; D009994:Osmolar Concentration; D011188:Potassium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*; D012975:Sodium Isotopes
D002021:Buffers; D002859:Chromium Isotopes; D007552:Isotonic Solutions; D012975:Sodium Isotopes; D012964:Sodium; D011188:Potassium