[Further improvement of the ACD-AG protective solution for blood. III. Improvement of the oxygen transport function of erythrocytes in sorbitol xylitol pyruvate solutions with elevated Ph].

If the pH value in the ACD or in the ACD-AG storage solution is enhanced, the glucose in the autoclaving with undergo a caramelizing process. For this reason glucose was replaced by sorbite in the storage solutions with a pH value of 6.0 and additions of xylitol and pyruvate. The initial pH value in the blood amounted to 7.3. The content of 2.3 DPG of the erythrocytes remained fully preserved in the blood with sorbitol and additions of xylitol and pyruvate during the first 2 weeks of storage and decreased to 30% only in the third week. There were only slight amounts of 2.3 DPG in the ACD-AG blood at that time of storage. Up to the third week of storage the ATP content of erythrocytes as well as the haemoglobin level in the plasma revealed no essential differences between stored blood with sorbitol and xylitol as a substrate or glucose + xylitol respectively. The quick decrease of the ATP level to zero and the simultaneous strong increase of haemolysis in the sorbitol blood within the fourth week of storage is discussed in connection with a lowering of the NAD/NADH2 quotient. For the purpose of keeping the 2.3 DPG level of erythrocytes a storage solution with sorbite and xylitol (ASCX-AG-Pyr 10mM) seems to be well suited for a storing time of 2---3 weeks at first.