Blood Leucocyte Enzymes: III. DIURNAL RHYTHM OF ACTIVITY IN ISOLATED LYMPHOCYTES OF NORMAL SUBJECTS AND CHRONIC LYMPHATIC LEUKAEMIA PATIENTS

Abstract

The activities of glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate: NADP oxidoreductase, G6PD), 6-phosphogluconate dehydrogenase (6 phospho-D-gluconate: NADP oxidoreductase, 6PGD), lactate dehydrogenase (D-lactate: NAD oxidoreductase, LDH), glutamate oxaloacetate transaminase (L-aspartate: 2-oxoglutarate aminotransferase, GOT) and hexokinase (ATP: D-hexo-7-phosphotransferase, Hx) were measured over 24 h in isolated lymphocytes of normal subjects and white cells of patients with chronic lymphatic leukemia (CLL). The activity patterns of all enzymes in the normal lymphocytes were similar. A computed pattern of all results exhibited a circadian rhythm of activity with the highest level at 16.00 h. Oscillations in the activities of the same enzymes in CLL cells differed among patients, although all enzymes of the same individual showed a similar diurnal rhythmic pattern. All peaks in this group appeared between 20.00 and 08.00 h. The possible importance of these observations in setting up therapeutic schedules was raised.