beta-Glucosidase and beta-galactosidase in primary cultures of rat astrocytes: comparison to the brain enzymes.
In primary astrocyte cultures beta-glucosidase (EC 3.2.1.21) and beta-galactosidase (EC 3.2.1.23) showed pH optima and Km values identical to rat brain enzymes, using methylumbelliferyl glycosides and labeled gluco- and galactocerebrosides as substrates. The activities of both glycosidases increased in culture up to 3-4 weeks. In rat brain only galactosidase increased; glucosidase activity declined between 12-20 days after birth. The specific activities were two- to sixfold higher in astrocyte cultures than in rat brain. These activities were not due to uptake of enzymes from the growth medium. Secretion of beta-galactosidase, but not beta-glucosidase nor acid phosphatase could be demonstrated. These results support the suggestion of a degradative function for astrocytes in the brain.
D000818:Animals; D001253:Astrocytes / Q000201:enzymology*; D001921:Brain / Q000201:enzymology*; D002478:Cells, Cultured; D003470:Culture Media; D005696:Galactosidases / Q000032:analysis*; D005959:Glucosidases / Q000032:analysis*; D051381:Rats; D011919:Rats, Inbred Strains; D013997:Time Factors; D001616:beta-Galactosidase / Q000032:analysis*; D001617:beta-Glucosidase / Q000032:analysis*
D003470:Culture Media; D005696:Galactosidases; D005959:Glucosidases; D001617:beta-Glucosidase; D001616:beta-Galactosidase