Kidney Enzymes of Gluconeogenesis, Glycogenesis, Glycolysis and Direct Oxidation.

Abstract

Summary The present work described the cellularity, nitrogen content and kidney enzymes involved in gluconeogenesis, glucose production, glycogenesis, glycolysis and direct oxidative pathway in kidney cortex. The results were compared with values found in the liver. The kidney contained 50% more cells per unit weight; however, the average kidney cell contained only about half the nitrogen content found in the liver cell. These studies demonstrated that the enzyme systems involved in glycolysis and gluconeogenesis, phosphohexose isomerase, lactic dehydrogenase, glucose-6-phosphatase and fructose-1,6-diphosphatase, are present in the kidney cortex at relatively high levels. On the other hand, the low activities for kidney phosphoglucomutase, glucose-6-phosphate dehydrogenase and 6-phos-phogluconate dehydrogenase suggest that this tissue has poor glycogenic and direct oxidative pathways in comparison with the metabolic pathways of the liver. This investigation revealed a distinct carbohydrate enzyme pattern in kidney cortex and showed that the activities of these enzymes as determined in tissue homogenate and supernatant fluid can be well correlated with studies on the relative importance of glucose metabolic pathways as elucidated by isotope techniques on kidney slices.