APPLICATION OF HIGH-FIELD LOCALIZED IN-VIVO H-1 MRS TO STUDY BIOCHEMICAL-CHANGES IN THE THIAMIN DEFICIENT RAT-BRAIN UNDER GLUCOSE-LOAD

In vivo, volume-selected H-1 NMR spectroscopy employing the SPACE tech nique was used to monitor biochemical changes in the thiamin deficient rat brain in response to glucose loading. The concentrations of brain N-acetylaspartate, glutamate/glutamine/gamma-aminobutyric acid, lacta te and glucose differed significantly from those of control animals. T he results are consistent with a metabolic block at the reaction catal yzed by the thiamin dependent enzyme alpha-keto glutarate dehydrogenas e soon after the onset of neurological symptoms of thiamin deficiency, and a further block at pyruvate dehydrogenase arising late in the cou rse of thiamin deficiency.