Effect of X-Irradiation on the Biochemical Maturation of Rat Cerebellum: Metabolism of [ 14 C]Glucose and [ 14 C]Acetate

The effect was studied of selective X-irradiation of the cerebellum (100 R daily in the first 10 days after birth) on the maturation of glucose metabolism and the development of metabolic compartmentation, in 10-, 16-, and 23-day-old rats by using, respectively, [2-¹⁴ C]glucose and [1-14 C]acetate (40 μCi/100 g body weight each) as precursors. At day 10 significant changes, in comparison with the unirradiated controls, were observed: aspartate and γ-aminobutyrate, respectively, contained 36% and 64% more and glutamine 42% less glucose-carbon combined in amino acids; the glutamine/glutamate specific radioactivity ratio (RSA) was 25% less, and the conversion of both glucose and acetate carbons into acid-insoluble constituents was markedly reduced. However, in the postirradiation period both the conversion of glucose carbon into amino acids, and the RSA of glutamine after the administration of [14 C]acetate increased in a more or less normal fashion, although ce...