Alterations of Erythrocyte Lactate Dehydrogenase in Man

Abstract

Erythrocyte preparations from normal men and women contain 5 isoenzymes of lactate dehydrogenase in constant proportions. LDH-5 is found exclusively in younger cells, and LDH-1 is the predominant fraction of aged erythrocytes. The apparent increase of LDH-1 in aged cells represents loss of activity of isoenzymes containing labile M subunits and not synthesis of H subunits. When erythrocyte isoenzymes from patients with hematologic disease are assayed, increases in LDH-5 indicate active or hyperactive erythroid tissue, and absence of this fraction suggests nonfunctioning tissue. An increase in the relative percentage of LDH-1 suggests the presence of an older cell population. Thus the analysis of erythrocyte LDH isoenzymes appears to have clinical value in rapidly assessing erythropoietic activity.

Isoenzymes of lactate dehydrogenase in human leukemic cells in culture treated with inducers of differentiation.

“…This conversion was accompanied by an increase of the anodic isoenzymes LD-1, LD-2, and LD-3. Also, these isoenzymes were found to be the predominant forms of normal erythrocytes, in agreement with a previous report (26). Thus, butyrate-treated K562 cells are similar to normal erythrocytes with respect to the ability to synthesize hemoglobin and lactate dehydrogenase .…”

Changes in the lactate dehydrogenase isoenzyme pattern during differentiation of rabbit bone-marrow erythroid cells

“…The loss of isoenzyme M4 is accompanied by a gradual relative increase of H4 during aging. Starkweather et al (1965) have proposed that isoenzyme M4 might be a measure of the developmental stage of the erythrocyte. Thus isoenzyme M4 may be necessary for the dividing cell, but not important for the metabolic functioning of the mature cell.…”

“…In younger cells, two additional faint bands migrating more slowly than the main bands were observed. An increase in human erythrocyte isoenzyme LDH 5 has been reported to indicate active or hyperactive erythroid tissue (Starkweather et al, 1965). Plagemann et al (1960) have shown that rabbit skeletal muscle is a tissue containing only the slowest-migrating isoenzyme M4, whereas rabbit heart muscle and erythrocytes contain only the fastest-migrating isoenzyme H4.…”

Biochemical alterations in patients with acute leukaemia

“…There are data in literature describing high levels of serum uric acid (13) and lactate-dehydrogenase (14) in patients with acute myeloid leukaemia, especially those with higher proportion of monocytoid cells. It was supposed that elevated value of uric acid might be the consequence of chemotherapeutic cytolytic effect.…”

“…It was supposed that elevated value of uric acid might be the consequence of chemotherapeutic cytolytic effect. There are also some data on the frequently high levels of sodium, potassium, calcium and hydrogen ione in sera of patients with acute leukaemia; some authors, however, have found lower values of parameters mentioned (14,15). On rare occasions a profound hyponatraemia may be found due to disturbance of antidiuretic hormone (ADH) secretion, or a significant hypernatraemia due to diabetes insipidus.…”