We examined the evolution of 1H-NMR detectable metabolites in rat cerebellum from the postnatal day 1-25, a period associated with intense metabolic changes as well as physiological and morphological modifications. The unexpected result reported here is the existence of a high concentration of acetate in neonatal rat cerebellum, progressively decreasing with age and maturation. In contrast, the cerebellum content of various metabolites such as N-acetyl-L-aspartate (NAA), glutamate, and aspartate increases from the first day onward.