P-31 MAGNETIC-RESONANCE SPECTROSCOPY STUDY OF CEREBRAL METABOLISM IN DEVELOPING DOG BRAIN AND ITS RELATIONSHIP TO NEURONAL FUNCTION

Cerebral metabolism and neuronal function of prefrontal brain cortex were studied in 6 dog litters from birth to 3 months of age. Noninvasive phosphorus magnetic resonance spectroscopy (P-31-MRS) was used to observe longitudinal biochemical changes in the phosphorus compounds associated with cerebral metabolism. Neurological tests, examining reflex, motor and sensory nerve function, were performed in conjunction with the P-31-MRS study. During the neonatal period, exponential increases in PCr, P(i), and phophodiesters preceded neurological changes. Phosphomonoesters showed an exponential, nearly linear, decrease and PCr/P(i) was maintained during the 3-month period. Developmental increases in high energy phosphates and the maintenance of PCr/P(i) indicate that the increased energy demands of the developing animal are met by increased mitochondrial function (ATP turnover).