PARTITION OF ADENOSINE TRIPHOSPHATASE IN INTRACELLULAR FRACTIONS OF MATURE AND IMMATURE RAT CEREBRUM

Abstract

Experiments in which infant and adult rat cerebrum were fractionated by differential centrifugation afford evidence that differences exist between comparable fractions from immature and mature nervous tissue with respect to a number of properties. These include differences in layering characteristics, and in the partition of total nitrogen and of calcium and magnesium activated adenosine triphosphatase (ATPase) activities. The total nitrogen content and Ca and Mg ATPase contents of the supernatant fraction of infant cerebrum are strikingly higher than those of the comparable fraction from adult cerebrum. Also, the "specific activity" of ATPase in two of the larger cytoplasmic particle fractions from infant cerebrum is higher than in comparable adult fractions.