Thesis Abstracts 1999

The cerebral metabolic activity of glucose and ketones was compared in ketotic rats with insulin-dependent diabetes mellitus (IDDM) and in normal controls. In the IDDM rats, ketosis had been present < 12 hours and the diabetes was of recent onset. After sufficient infusion of labeled [1-13C]glucose to achieve steady-state levels, the ratio of the fractional enrichment of the metabolites [4-13C]glutamate and [3-13C]alanine was determined by NMR spectroscopy. This ratio was higher in the normal (0.65) than in the IDDM (0.49) group (p < .005), indicating that ketones provide a significant contribution to oxidative metabolism in brain during the early phase of diabetic ketosis.