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Further observations on the activation of lysosomal acid alpha-glucosidase by cortisone derivatives.

ABSTRACT: 1. Cortisone acetate activates the acid alpha-glucosidase in rat liver slices and in isolated liver lysosomes. 2. The reaction is steroid specific and moreover does not occur with lysosomal acid phosphatase or beta-galactosidase. 3. After pretreatment of the lysosomes with cortisone, substrate (maltose) binding to the soluble lysosomal acid alpha-glucosidase is not affected, but the steroid does increase the V(max.) value. Membrane-bound enzyme is not activated by cortisone. 4. 4-[(14)C]Cortisone is preferentially bound to the lysosomal membrane and the possible involvement of this structure in the activation phenomenon is discussed.

SUBMITTER: Bourne EJ

PROVIDER: S-EPMC1177606 | biostudies-other | 1973 Mar

REPOSITORIES: biostudies-other

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Studies on type II glycogenosis. Effects of cortisone derivatives on acid -glucosidase.

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