Erythrocyte changes in aqueous polyethylene glycol solutions containing sodium chloride

The behavior of rabbit erythrocytes in aqueous solutions of polyethylene glycol 300 (I) and polyethylene glycol 400 (II) containing sodium chloride was investigated during 2-120 min incubation at 37 degrees. No hemolysis was found in I (0-10.1%) and II (0-12.9%) solutions in the presence of sodium chloride (0.45-1.35%), but prelytic potassium ion loss and changes in the appearance of the erythrocytes proceeded with the passage of time. The potassium ion loss increased with increasing concentration of polyethylene glycol and/or sodium chloride. The mean cellular volume of erythrocytes decreased temporarily (during the first 2 min) in both I (6.7%) and II (8.6%) solutions containing sodium chloride (0.68-1.35%), and then increased progressively to the same value as that determined by solution of sodium chloride at the same concentration but without polyethylene glycol (approximately 30 and 120 min in I and II solutions, respectively). Both I (10.1%) and II (12.9%) induced a stomatocytic transformation of erythrocytes, but at the higher concentrations (0.9-1.35%) of sodium chloride, II accelerated the progress of spontaneous transformation of erythrocytes, but at the higher concentrations (0.9-1.35%) of sodium chloride, II accelerated the progress of spontaneous transformation to echinocytes. The results indicate that these solutions were not isotonic with rabbit erythrocytes.