Red Blood Cell Potassium Research Articles

Energy requirements for ion transport in steady-state systems.

SEVERAL investigators1–3 have attempted to calculate the energy required to maintain steady-state exchanges of ions between animal tissues and their environments. Thus, Krebs, Eggleston and Terner1 concluded that about 2.5 per cent of the respiratory energy was required for potassium exchange in brain cortex slices at 40° C., and Bernstein2 calculated that the steady-state exchanges of sodium and potassium in red blood cells at 37° C. may require up to one-third of the free energy from glycolysis. These calculations1,2 were based on the assumptions that there was 100 per cent efficiency in the utilization of metabolic energy for ion transport, that the losses and gains of the same ion were independent, and that the movements of different ions were also independent of one another. These assumptions are not necessarily valid.