Lysosomal Acid Hydrolases in Developing Huml Brain Regions

Abstract

.beta.-D-Glucosidase, .beta.-D-glucosaminidase, acid phosphatase and .beta.-D-galactosidase were monitored in the human fetal brain at different gestational periods. Glucosidase specific activity in all brain regions exhibits 2 peaks, at 8 and 32 g fetal wt. Acid phosphatase exhibits very high specific activity in all brain regions at 5 g, but the cerebellar activity forms a peak at 220 g fetal wt, the midbrain at 135 g, and the spinal activity at 760 g. .beta.-D-Glucosaminidase has a peak at 220 and 660 g in the midbrain, and .beta.-D-galactosidase specific activity is highest in the cortex and cerebellum in late gestation (neuronal differentiation phase). The midbrain medulla and the spinal cord show peak activity at 8 and 220 g fetal wt. An inter- and intraregional heterogeneity of acquisition for these enzymes apparently occurs in human brain ontogeny.