[Acid mucopolysaccharides in the postnatal maturation of the brain]

Using the reliable method of separating cell fractions and myelin from the rat brain tissue during postnatal ontogenesis, we investigated changes in the content of acid mucopolysaccharides (AMPS) as macromolecular constituents in cell elements, neuronal and glial fractions, on one hand, and subcellular structures, myelin, on the other. During postnatal ontogenesis, the content of rat brain AMPS displays marked fluctuations not only in toto but also within all cell fractions and myelin. These changes were the highest in glial fractions, somewhat lower in neuronal fractions and the lowest in myelin fractions at the beginning of myelination. During the period of intensive myelination, the level of AMPS decreases markedly in glial fractions but increases in myelin fraction. In the late period of postnatal development, myelin contains 60% of the rat brain AMPS.