Subject(s)
Carbohydrate Metabolism, Inborn Errors/pathology , Mitochondrial Myopathies/pathology , Carbohydrate Metabolism/physiology , Carbohydrate Metabolism, Inborn Errors/classification , Carbohydrate Metabolism, Inborn Errors/genetics , Fructose-Bisphosphate Aldolase/deficiency , Fructose-Bisphosphate Aldolase/genetics , Glycogen/deficiency , Glycogen/metabolism , Glycogen Storage Disease Type II/genetics , Glycogen Storage Disease Type II/metabolism , Glycogen Storage Disease Type III/genetics , Glycogen Storage Disease Type III/metabolism , Glycogen Storage Disease Type IV/genetics , Glycogen Storage Disease Type IV/metabolism , Glycogen Storage Disease Type V/genetics , Glycogen Storage Disease Type V/metabolism , Glycogen Storage Disease Type VII/genetics , Glycogen Storage Disease Type VII/metabolism , Glycogen Storage Disease Type VIII/genetics , Glycogen Storage Disease Type VIII/metabolism , Humans , L-Lactate Dehydrogenase/deficiency , Mitochondrial Myopathies/classification , Mitochondrial Myopathies/genetics , Phosphoglycerate Kinase/deficiency , Phosphoglycerate Mutase/deficiency , Phosphoglycerate Mutase/genetics , Phosphorylase b/deficiencyABSTRACT
We describe an Arab girl with complete absence of phosphorylase b kinase activity in the liver, symptomatic hypoglycemia, and persistently elevated serum aminotransferase values whose symptoms did not lessen with age; sequential liver biopsies showed progression to cirrhosis. Cirrhosis could not be ascribed to any other known cause. We conclude that type IX glycogenosis is not always associated with a benign outcome.
Subject(s)
Glycogen Storage Disease/complications , Liver Cirrhosis/complications , Liver/enzymology , Phosphorylase Kinase/deficiency , Phosphorylase b/deficiency , Child, Preschool , Consanguinity , Culture Techniques , Female , Glycogen Storage Disease/diagnosis , Humans , Liver/physiopathology , Liver Cirrhosis/physiopathology , Liver GlycogenABSTRACT
The erythrocyte aspartate aminotransferase and renal and intestinal glycogen phosphorylase activities in rats are determined as dependent on their provision with vitamin B6. It has been shown that the aspartate aminotransferase activity decreases and the shape of the aspartate concentration-activity curve changes in the vitamin B6-deficient animals. The B6 insufficiency does not affect the intestinal mucosa glycogen phosphorylase. However the renal phosphorylase activity decreases by 30 percent in the vitamin B6 deficient rats. It occurs due to changes in the affinity of phosphorylase A and B to glucose-1-phosphate but not to AMP. The activation of these investigated enzymes by exogenous pyridoxal phosphate reveals no essential differences between the vitamin B6-deficient and normal rats. The possible causes of the observed changes in the aspartate aminotransferase and phosphorylase activity are discussed.
Subject(s)
Aspartate Aminotransferases/deficiency , Phosphorylase a/deficiency , Phosphorylase b/deficiency , Phosphorylases/deficiency , Vitamin B 6 Deficiency/enzymology , Animals , Aspartate Aminotransferases/blood , Diet , Erythrocytes/enzymology , Humans , Kidney/enzymology , Kinetics , Male , Phosphorylase a/blood , Phosphorylase b/blood , Rats , Rats, Inbred Strains , Species SpecificityABSTRACT
A 6-year-old boy was examined with the dual purpose of establishing whether he had malignant hyperthermia (MH) and to investigate his complaint of excessive muscle fatiguability. In the course of such investigations, McArdle's disease was diagnosed, and the patient was also identified as an MH-positive reactor.
Subject(s)
Glycogen Storage Disease Type V/diagnosis , Malignant Hyperthermia/diagnosis , Phosphorylase b/deficiency , Phosphorylases/deficiency , Child , Fatigue , Glycogen Storage Disease Type V/complications , Humans , Male , Malignant Hyperthermia/complications , Malignant Hyperthermia/physiopathology , Muscles/physiopathologyABSTRACT
Glucose production was measured using stable isotopic techniques in two patients with phosphorylase b kinase deficiency before and after oral ethanol (0.75 g/kg). Glucose production was normal before the ethanol. In one patient, who did not take the full dose of ethanol, glucose production rose initially and then fell. In the other, glucose production fell steadily and in both patients blood lactate concentrations rose. Blood glucose concentrations decreased. Patients with this enzyme deficiency are dependent on the gluconeogenic pathway when fasting and, therefore, ethanol may be potentially hazardous.
Subject(s)
Blood Glucose/biosynthesis , Ethanol/pharmacology , Gluconeogenesis/drug effects , Phosphorylase Kinase/deficiency , Phosphorylase b/deficiency , Phosphorylases/deficiency , Adolescent , Alcohol Drinking , Humans , Kinetics , Lactates/blood , MaleABSTRACT
A 35-year-old man had severe exercise intolerance and cramps. Venous blood lactate did not rise after ischemic exercise, and electromyographically silent contracture of hand muscles appeared. Histochemistry and electronmicroscopy of a muscle biopsy revealed subsarcolemmal and intermyofibrillar accumulation of glycogen. Biochemical studies showed moderately increased amount of glycogen. Total phosphorylase activity was normal, but the active form "a" was 27% of normal. Phosphorylase kinase activity was 12% of the normal value and was normal in leukocytes and erythrocytes.
