An Effect of Sugars on Fluid Entry into Erythrocytes

Abstract

WHEN human erythrocytes are suspended in a salt solution containing glucose, the sugar enters the cells and establishes an osmotic gradient across the cell membrane. Consequently water follows the glucose into the erythrocytes, causing the cells to swell and ultimately to haemolyse. Some investigators^1–4 have used the rate of swelling or haemolysis as a measure of rate of sugar entry into the cells. An example of the results obtained by this method is shown in Fig. 1. Since the total osmolarity of the suspend ing medium was not changed on addition of the sugar solutions in this experiment, the observed haemolysis can be ascribed to sugar entry into the cells. However, the kinetic interpretation of such data seems uncertain, for we observed that sugars also tend simultaneously to depress the rate of fluid entry into the erythrocytes.