Depletion and Regeneration of 2,3‐diphosphoglyceric Acid in Stored Red Blood Cells

Abstract
2,3‐diphosphoglyceric acid appears to be an important regulator of the oxygen dissociation curve of hemoglobin in intact red blood cells. The rate of loss of 2,3‐DPG under various storage conditions therefore was investigated. 2,3‐DPG disappeared rapidly from conventional preservative media, CPD, and ACD solutions. After only two weeks' storage, 65 per cent to 85 per cent of erythrocyte 2,3‐DPG had been lost from ACD‐stored blood and slightly less from CPD‐stored blood. Although the addition of adenine to ACD solution aided in the maintenance of ATP levels, it hastened the rate of loss of 2,3‐DPG. The rate of 2,3‐DPG depletion was strongly dependent on pH. In more alkaline storage media, levels of this compound were relatively well maintained for as long as two, or even three weeks. However, under these circumstances ATP maintenance was less satisfactory. The levels of 2,3‐DPG and ATP in red blood cells incubated in fresh plasma at 37 C, pH 7.4, to simulate the conditions after reinfusion of stored cells also was investigated. ATP levels remained relatively stable under these circumstances and 2,3‐DPG levels were restored gradually. However, the repletion of 2,3‐DPG was sufficiently slow so that even after eight hours only approximately one third of the 2,3‐DPG which had been lost was regenerated. Thus, stored blood may fail to transport oxygen efficiently for many hours after reinfusion.