The influence of branched chain aminoacids and their ketoderivatives on renal gluconeogenesis.

Isolated kidney tubules served as a model to investigate the direct effect of branched chain aminoacids and their ketoderivatives on gluconeogenesis. The data presented in this paper demonstrate that the ketoderivatives rather than the branched chain aminoacids themselves inhibit renal glucosesynthesis from various precursors entering the glucogenic pathway at different levels. Though the point of the inhibitory attack of ketoacids could not be localized, an impairement of the kidney cortex to respond to metabolic acidosis with an increase of gluconeogenesis is evident from the present data. The relevance of the presented data concerning the production of hypoglycemia and metabolic acidosis in leucine induced hypoglycemia and maple syrup urine disease is discussed.