Alterations of Erythrocyte Lactate Dehydrogenase in Man

ACTATE DEHYDROGENASE (LDH) from tissues of man can be sepa-rated by electrophoretic technics into isoenzymic fractions.’4 Normal tissues contain five distinct proteins with LDH activity in constant propor-tions, but these fractions fluctuate markedly in a number of pathological conditions. This report is concerned with erythrocyte LDH isoenzyme changes observed in certain hematological disorders, and the relationship of these changes to tile dynamic state of erythropoiesis. MATERIALS AND METHODS a. Nicotinamide adenine dinucleotide and phenazine methosulfate were obtained from the Sigma Chemical Company. b. Tetra intro blue tetrazolium was purchased from Nutritional Biochemical Corporation. c. Sodium L+ lactate was a product of Mann Research Biochemicals. d. Agan gels were prepared using Difco “Purified ” Agar. Blood was obtained by venipuncture, and the leukocytes removed by dextran sedimenta-tion.5 The erythrocytes were washed 3 times in 4 volumes of 0.156 M sodium chloride