Studies of gluconeogenesis were carried out with isolated tubules prepared from the renal cortex of fasted rats. A study of the metabolic characteristics of this preparation upon incubation at 37° revealed a sustained respiratory rate, a constancy of ATP levels, and a linear rate of gluconeogenesis. Virtually no glucose synthesis was observed unless appropriate substrates were added; succinate and α-ketoglutarate were the most effective precursors. The addition of phenformin to the suspension of isolated tubules led to a decline of O2 uptake and ATP content in the absence and in the presence of added substrate. In the presence of succinate, there was a close correlation between the ATP content and the rate of gluconeogenesis. The data indicate that the phenformin-induced inhibition of gluconeogenesis is secondary to limitation of ATP generation rather than a direct effect on the enzymatic sequence leading to new glucose formation or to limited availability of reducing equivalents.
Skip Nav Destination
Article navigation
Original Contributions|
January 01 1973
Gluconeogenesis in Renal Cortical Tubules: Effect of Phenformin
Edwin E Gordon, M.D.;
Edwin E Gordon, M.D.
Department of Medicine, New York University Medical Center
New York, New York 10016
Search for other works by this author on:
Maria de Hartog
Maria de Hartog
Department of Medicine, New York University Medical Center
New York, New York 10016
Search for other works by this author on:
Citation
Edwin E Gordon, Maria de Hartog; Gluconeogenesis in Renal Cortical Tubules: Effect of Phenformin. Diabetes 1 January 1973; 22 (1): 50–57. https://doi.org/10.2337/diab.22.1.50
Download citation file: