PHOSPHORYLATED CARBOHYDRATE INTERMEDIATES OF THE HUMAN ERYTHROCYTE DURING STORAGE IN ACID CITRATE DEXTROSE. I. EFFECT OF THE ADDITION OF INOSINE AT THE BEGINNING OF STORAGE*

Abstract

The phosphorylated carbohydrate intermediates of the human erythrocyte were assayed by ion-exchange chromatography after 0, 2, 4, 6, and 8 weeks of storage at 4[degree]C in acid citrate dextrose (ACD) with or without inosine (I). The breakdown of diphosphoglycerate and adenosine triphosphate accounted for most of the fall in concentration of organic phosphate and the associated increase in inorganic phosphate. These changes were retarded by the presence of inosine in the incubating solution. Adenosine diphosphate (ADP), which was present in comparatively small amounts, showed a moderate increase at 4 weeks followed by a decline in concentration to 1/3 the initial level when the blood was stored in ACD. In ACDI the level of ADP increased slightly at both 4 and 8 weeks. Inosine mono-phosphate was found in small amounts only at 4 weeks in ACD and at 4 and 8 weeks in ACDI. Fructose diphosphate was not found at any time in either sample. Glucose diphosphate was surprisingly constant in concentration in ACD blood and increased somewhat in ACDI. Of possible intermediates of the pentose shunt which might be expected from the metabolism of inosine, only sedoheptulose-7-phosphate was found. In the presence of inosine, glucose-6-phosphate rose to a maximum several-fold higher than that found in the normal erythrocyte. The results are compared with those of a previous similar study of stored rabbit erythrocytes.