STUDIES ON THE PRESERVATION OF BLOOD: V. THE INFLUENCE OF THE HYDROGEN ION CONCENTRATION ON CERTAIN CHANGES IN BLOOD DURING STORAGE

Abstract

The hexokinase of the erythrocyte has two optima of activity, a pronounced one at pH 7.8 and a lesser one at pH 6.0. Glycerate-2,3-diphosphatase of the red cell similarly has two sharp optima, at pH 7.0 and 8.1, respectively. From pH 7.2 to 7.8 the activity of the diphosphatase is very low. During storage of blood with the citrate–dextrose (CD) medium at 4 °C. the pH of the samples falls from about pH 7.4 to 6.9, by the end of the fourth week. When blood is preserved with the acidified citrate–dextrose (ACD) medium, the pH falls from about 7.1 to 6.5 in the same period. The content of 2,3-diphosphoglycerate and the diminution in the activity of the hexokinase of the red cells are related to the change in the pH of the blood during storage. The significance of these changes is discussed.