title: Effect of acute hyperglycemia on glucose metabolism in skeletal muscles in IDDM patients.
abstract: The effect of acute hyperglycemia on glucose metabolism in skeletal muscles was assessed during replacement insulin infusion in 11 patients with insulin-dependent diabetes mellitus (IDDM). With a primed continuous [3-3H]glucose infusion and indirect calorimetry, glucose metabolism was assessed during a basal period (plasma glucose [PG] 5 mM) and during a hyperglycemic period (4-h i.v. glucose infusion, PG 12.1 mM). Biopsies were taken from the vastus lateralis muscle during both periods. On a control day, glucose metabolism was assessed in 10 patients during a basal period (PG 5.2 mM) and after 4 h with no glucose infusion (PG 4.2 mM). Nonoxidative glucose disposal increased during hyperglycemia (32 +/- 7 vs. 51 +/- 9 mg.m-2.min-1, P less than 0.05), whereas glucose oxidation remained constant. On the control day, nonoxidative glucose disposal decreased from the basal to the second (control) period (33 +/- 7 vs. 22 +/- 6 mg.m-2.min-1, P less than 0.05), and glucose oxidation remained constant. The activity of glycogen synthase in muscle biopsies (fractional velocities [0.1 and 10 mM glucose 6-phosphate (G6P)]) decreased slightly during hyperglycemia (18 +/- 2 vs. 12 +/- 2%, P less than 0.05) and on the control day (26 +/- 4 vs. 20 +/- 3%, P less than 0.05). Hyperglycemia increased the intracellular concentration of free glucose, corrected for estimated extracellular glucose (0.56 +/- 0.11 vs. 1.43 +/- 0.19 mM, P less than 0.01), G6P (0.14 +/- 0.04 vs. 0.23 +/- 0.08 mM, P less than 0.02), and lactate (2.88 +/- 0.33 vs. 4.46 +/- 0.61 mM, P less than 0.05), whereas these substrate concentrations remained constant on the control day.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Odense University Hospital, Department of Internal Medicine, Denmark.
authors.forename: A
authors.initials: A
authors.lastname: Vaag
authors.forename: O
authors.initials: O
authors.lastname: Hother-Nielsen
authors.forename: P
authors.initials: P
authors.lastname: Skött
authors.forename: P
authors.initials: P
authors.lastname: Andersen
authors.forename: E A
authors.initials: EA
authors.lastname: Richter
authors.forename: H
authors.initials: H
authors.lastname: Beck-Nielsen
mesh_terms: D000208:Acute Disease; D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D003922:Diabetes Mellitus, Type 1 / Q000378:metabolism*; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006006:Glycogen Synthase / Q000378:metabolism; D006801:Humans; D006943:Hyperglycemia / Q000378:metabolism*; D007328:Insulin / Q000097:blood; D008297:Male; D009132:Muscles / Q000378:metabolism*; D010084:Oxidation-Reduction
chemical_list: D001786:Blood Glucose; D007328:Insulin; D006006:Glycogen Synthase; D005947:Glucose