THE LACTIC DEHYDROGENASE ACTIVITY AND PYRIDINE NUCLEOTIDE CONTENT OF HUMAN BLOOD CELLS IN ANEMIA

Abstract

The lactic dehydrogenase activity and the pyridine nucleotide content of the blood cells (PN/BC) of two normal subjects and 12 patients with various degrees of anemia was measured to determine whether the previously reported elevated PN/BC values in anemia are related to an altered metabolic activity of the cells. In 12 well nourished subjects it was found that the PN/BC, expressed in μgm. DPN per gm. of hemoglobin, was elevated in proportion to the severity of the anemia and that this increase was accompanied by a proportional rise in the cellular lactic dehydrogenase activity. The low PN/BC of two poorly nourished patients was accompanied by correspondingly low lactic dehydrogenase levels. The correlation coefficient for the relationship between the lactic dehydrogenase and PN/BC values for all the subjects was + 0.89 and was considered significant since P < 0.01. The results suggest that the potential activity of an important enzymatic step in erythrocyte glycolysis is increased in anemia in proportion to the decrease in the hemoglobin concentration and the fall in the hematocrit. The increased PN/BC under these conditions is probably a reflection of an elevated cellular diphosphopyridine nucleotide concentration.