Sodium and Potassium Changes in Blood Bank Stored Human Erythrocytes

Abstract

Storage of red cells for 3 wk at 4.degree. C under blood bank conditions resulted in a rise in intracellular Na+ and a fall in intracellular K+ with concomitant opposite changes in Na+ and K+ levels in the suspending plasma. A decline in red blood cell ATP during the storage period apparently did not contribute to the changes. Increasing red blood cell ATP to levels 2-3 times normal did not prevent the cation changes from occurring. When assayed at 37.degree. C with added Mg2+, ouabain-sensitive membrane ATPase activity and kinetics of activation by Na+ were unaffected by the 3 wk period of cold storage. When assayed at 4.degree. C without added Mg2+, simulating the conditions of storage, ATPase activity was negligible. Na and K did not change when red blood cells with normal ATP content were stored at 20-24.degree. C even without added Mg2+. A major cause for the development of cation changes in the red blood cell during blood bank storage is the temperature which inhibits membrane ATPase, allowing cations to leak unopposed into and out of the red blood cells.