Changes in hexokinase and glucose-6-phosphate dehydrogenase in red cells during hypo and hyperthyroidism

Activities of hexokinase and glucose-6-phosphate dehydrogenase have been measured in red blood cells from thyroidectomized, triiodothyronine treated and hyperthyroid rats. After thyroidectomy, significant decrease in the activities of hexokinase and glucose-6-phosphate dehydrogenase was observed as compared to controls. The effects were reversed with triiodothyronine administration to the thyroidectomized rats. Hyperthyroidism increased both enzymes. The observations further confirm the hypermetabolic effects of thyroid hormones on the cellular metabolism.