A study of ³H‐L‐fucose‐containing glycoproteins of the crude synaptosomal fraction, obtained from rat brain regions at various ages

The frontal cortex showed a marked elevation of incorporation of H‐L‐fucose into glycoproteins of the crude synaptosomal fraction at 9 days of age. The effect was observed at both 8 and 24 hr after intraperitoneal administration of radioactive fucose. The elevation was absent in the 1, 5, 16, and 25‐day‐old frontal cortices. It was also absent in the hippocampus and cerebellum at all ages studied. Fucose‐labeled glycoproteins of high molecular weight in the crude synaptosomal fraction, as separated by polyacrylamide gels, were preferentially labeled in the hippocampus, frontal cortex, and cerebellum at all ages studied. In general, these glycoproteins became less prominent in the oldest animals studied (25 days). However, the relative amount of these glycoproteins varied with age of the animal, time between administration of isotope and sacrifice, and with the brain areas studied.