RESPIRATORY EFFICIENCY AND FLEXIBILITY OF ERYTHROCYTES STORED IN ACID-CITRATE-DEXTROSE SOLUTION

1. Measurements have been made of the flexibility and respiratory efficiency of erythrocytes stored in acid‐citrate‐dextrose (ACD). 2. The rate of packing of stored blood, during centrifugation, indicates that the red blood cells are relatively inflexible. 3. Spectrophotometric observations, using the rapid‐mixing and stopped‐flow technique, indicate that the rate of egress of oxygen from HbO2 in these erythrocytes is significantly reduced. This is not due to a change of the chemical rate of dissociation of HbO2. 4. Neither factor is significantly reversed by resuspending the cells in Ringer‐Locke solution or adjusting to pH 7·4. 5. A small improvement is obtained by adding hypertonic NaCl or incubating the blood at 37° C for 1 hr. 6. Incubation with adenosine, 25 μ‐mole/ml. blood, at 37° C for at least 1 hr, restored both the respiratory function and flexibility to normal. © 1969 The Physiological Society