Studies on Erythrocyte Glycolysis: V. Change of the Glycolytic Intermediate Pattern of Reticulocytes during Maturation*

Abstract

The concentrations of glycolytic intermediates and adenine nucleotides in reticulocytes from rabbits which were induced by acetyl-phenylhydrazine injection, were analyzed and compared with those of the mature cells. The following changes were found to be correlated with the reticulocyte count of blood, when the samples were collected during the in vivo maturation of the cells: The concentrations of hexose-6-phosphates in reticulocytes are high compared with those of the mature cells, whereas those of fructose diphosphate, triose phosphates, mono-phosphoglycerates and phosphoenolpyruvate show little difference in reticulocytes and mature red cens. The concentration of α-glycerophos-phate is found to be extremely high compared with that in the mature cells. The content of ATP is high in reticulocytes, while that of 2,3-diphosphoglycerate is lower than that in the mature cells. The effect of acetylphenylhydrazine to mature rabbit erythrocytes incubated with glucose was studied to exclude the possibility that the above observations were caused by the reagent. The level of ATP as well as those of the hexose monophosphates decreased on the addition of acetylphenylhydrazine, while that of 3-phosphoglycerate increased. The lactate formation as well as the pattern of glycolytic intermediates and nucleotides in reticulocytes incubated in the presence of glucose and inorganic phosphate at pH 7.4 were analyzed. On the addition of cyanide, the concentrations of hexose 6-phosphates in the cells decrease and at the same time the lactate formation increases. This agrees with the observations made with other kind of cells. The addition of 2,4-dinitrophenol also causes an increase of the lactate formation with the concomitant decrease of the glycolytic intermediates including hexose 6-phosphates.