[Changes in erythrocyte size during swelling in hypo-osmotic media]

Swelling of erythrocytes in hypotonic media was considered. Taking into account the presence of surface rigidity in erythrocyte membranes an equation is proposed which describes a relationship between erythrocyte sizes and osmolarity of the suspension medium. Calculations carried out on the basis of this equation show that in the experiments when osmotic resistance of erythrocytes is estimated the mechanical properties of erythrocyte membranes are largely manifested. In many cases at their expense there seems to proceed the change of this index.