The effect of prostaglandin E2-induced echinocytic transformation on the potassium loss, viscosity and osmotic fragility of normal and sickle cell erythrocytes.

Prostaglandin E2 (PGE2)-induced discocyte leads to echinocytic transformation has no effect on the viscosity or osmotic fragility of normal or sickle cell erythrocytes. Membrane permeability, reflected as potassium efflux, is significantly affected in normal erythrocytes when greater than 90% of the cells are morphologically transformed to the echinocytic III stage (PGE2 concentration of 1--2x10(6) ng/ml blood). This potassium loss is significant in sickle erythrocytes when 50-70% of the cell population has been transformed (PGE2 concentration, 5x10(5) ng/ml blood). This change in membrane permeability represents one-half to one-third the flux that occurs with sickling (i.e., greater than 80% of the erythrocytes sickled).