THE EFFECTS OF NUCLEOSIDES ON THE RESISTANCE OF NORMAL HUMAN ERYTHROCYTES TO OSMOTIC LYSIS 1, 2

The investigations reported in this paper pro-ceeded on the hypothesis that maintenance of the structural integrity of the human erythrocyte is dependent on continued production and utilization of energy by the cell. In an attempt to test this hypothesis the susceptibility of fresh human eryth-rocytes to osmotic lysis was studied in terms of the influence of various compounds that might serve as substrates for energy yielding reactions within the erythrocyte. Particular attention was paid to glucose (3) and purine nucleosides (4, 7) which have been shown to prolong the viability of stored erythrocytes and to retard their progressive lysis and diminished resistance to hypotonic solutions. It may be noted, however, that the effectiveness of the purine nucleosides in the preservation of eryth-rocytes has recently been questioned (8). MATERIALS AND METHODS Blood freshly drawn from normal adults was defibri-nated and the erythrocytes were washed three times with about three volumes of isotonic sodium phosphate buffer (pH 7.3 to 7.4). Each washing was carried out with centrifugation in a Servall Refrigerated Angle Centri-fuge for 10 minutes at 1,600 G and at 40 C. (SS-1 rotor). The phosphate buffer was prepared to contain 3.76 grams NaHPO, HO and 11.62 grams NaHPO, in dis-tilled water in a final volume of one liter. A fifty pe