Metabolic Regulation of 2,3-DPG in Stored Red Blood Cells

The investigations carried out under this contract were aimed at attempting to find better mechanisms for maintenance of red cell 2,3-DPG levels during storage. The effect of 42 different compounds on red cell ATP and 2,3-DPG levels was studied. Of these oxalate, glyoxalate, ethyl oxaloacetate and L- phenylalanyl-L-alanine were found to improve 2,3-DPG levels. Glyoxalate and ethyl oxaloacetate exert their effect by conversion to oxalate. The latter compound has been shown to inhibit pyruvate kinase and in this way modifies red cell metabolism so as to cause an increase in red cell 2,3-DPG levels. L- phenylalanyl-L-alanine is rapidly hydrolyzed to phenylalanine and alanine, both of which also inhibit pyruvate kinase.