title: Adult-onset acid maltase deficiency: a postmortem study.
abstract: In a postmortem study of a patient with adult-onset acid maltase deficiency (AMD), morphological abnormalities were confined to skeletal muscle and consisted of a vacuolar myopathy. Acid maltase activity, however, was approximately 6% of normal in muscle, liver, and brain, and 3% of normal in heart. Kinetic characteristics, and inhibition by antibodies and Zn++, showed that the residual activity was "authentic" acid maltase. Neutral maltase activity was normal in muscle and liver, but decreased in brain (55% of normal) and heart (19% of normal). Although the relative decrease of acid maltase was similar in different tissues, absolute residual activity was lowest in skeletal muscle: this may explain the selective involvement of this tissue in late-onset AMD.
mesh_terms: D000328:Adult; D000367:Age Factors; D001921:Brain / Q000201:enzymology; D005087:Glucan 1,4-alpha-Glucosidase / Q000172:deficiency* / Q000378:metabolism; D005959:Glucosidases / Q000172:deficiency*; D006003:Glycogen / Q000378:metabolism; D006801:Humans; D008099:Liver / Q000201:enzymology; D008297:Male; D009132:Muscles / Q000201:enzymology; D009135:Muscular Diseases / Q000201:enzymology*; D015032:Zinc / Q000378:metabolism
chemical_list: D006003:Glycogen; D005959:Glucosidases; D005087:Glucan 1,4-alpha-Glucosidase; D015032:Zinc