IS OSMOTIC HEMOLYSIS AN ALL-OR-NONE PHENOMENON?

¹ From the Department of Physiology, University of Pennsylvania

1. Hemolysis produced by hypotonic sodium chloride is of an all-or-none type, that is, hemoglobin either fails to escape from the erythrocyte or does so completely up to the point permitted by the attainment of a diffusion equilibrium in the system.

2. The same all-or-none character is observed when, instead of permitting the hemolytic process to proceed to its original equilibrium position, it is stopped at an intermediate point by the addition of sodium chloride.

3. In hemolysis in solutions of penetrating substances such as glycerol and ethylene glycol, the final equilibrium obtained after checking the process by the addition of sodium chloride likewise indicates an all-or-none relationship.

4. In glycerol solutions the liberation of hemoglobin lags somewhat behind the disappearance of the cells and the final equilibrium is rather slowly attained.