Quantitative relationships between the concentration of proteins and the concentration of K+ and Na+ in red cell...

The concentration of K+ accumulated in and Na+ extruded from red blood cell ghosts are quantitatively correlated with the total protein contents of the ghosts with a linear correlation coefficient of +0.80. The straight line derived from the 43 sets of data on K+ accumulated in the presence of varying ghost proteins, when extrapolated to the protein content of a normal red blood cell, yields a total K+ content close to that actually found in normal red blood cells. This quantitative relationship agrees with the prediction of the AI hypothesis that there should be a stoichiometric relation between the K-adsorbing protein(s) and the concentration of K+ accumulated. In addition the data suggests that in red blood cells the protein providing most of the K+ adsorbing sites is hemoglobin. The apparent equilibrium distribution coefficient, or p-value, of Na+ dissolved in the ghost water at different protein concentrations and in intact red blood cells follows a pattern similar to that seen in solutions of gelatin and of oxygen-containing linear polymers.