Whole body glucose kinetics in type I diabetes studied with [6,6-2H] and [U-13C]-glucose and the artificial B-cell.
Dynamic aspects of whole body glucose metabolism were assessed in ten young adult insulin-dependent (type I) diabetic men. Using a primed, continuous intravenous infusion of [6,6-2H]glucose and [U-13C]glucose, endogenous production, tissue uptake, carbon recycling, and oxidation of glucose were measured in the postabsorptive state. These studies were undertaken after blood glucose had been maintained overnight at 5.9 +/- 0.4 mmol/L (n = 10), and on another night at 10.5 +/- 0.4 mmol/L (n = 4) or 15.2 +/- 0.6 mmol/L (n = 6). In the normoglycemic state, endogenous glucose production averaged 2.15 +/- 0.13 mg x kg-1 x min-1. This value, as well as the rate of glucose carbon recycling (0.16 +/- 0.04 mg x kg-1 x min-1) and glucose oxidation (1.52 +/- 0.16 mg x kg-1 x min-1) are comparable to those found in nondiabetic controls. In the hyperglycemic states at 10 or 15 mmol/L, endogenous glucose production was increased by 11% (P less than .01) and 60% (P less than .01) compared to the normoglycemic states, respectively. Glucose carbon recycling contributed only a small percentage to this variation in glucose production (15% at the 15 mmol/L glucose level). This suggests that if gluconeogenesis participates in the increased glucose output, it is not dependent on a greater systemic supply of three-carbon precursors. The increased rate of glucose production in the hyperglycemic state was quantitatively offset by a rise in urinary glucose excretion. Glucose tissue uptake, as well as glucose oxidation, did not vary between normoglycemic and hyperglycemic states.(ABSTRACT TRUNCATED AT 250 WORDS)
Darmaun
D
D
Hôpital Herold, Paris, France.
Cirillo
D
D
Koziet
J
J
Chauvet
D
D
Young
V R
VR
Robert
J J
JJ
D000293:Adolescent; D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D002247:Carbon Isotopes; D003903:Deuterium; D003922:Diabetes Mellitus, Type 1 / Q000378:metabolism*; D005943:Gluconeogenesis; D005947:Glucose / Q000493:pharmacokinetics*; D006801:Humans; D007328:Insulin / Q000494:pharmacology; D007332:Insulin Infusion Systems; D010084:Oxidation-Reduction
D001786:Blood Glucose; D002247:Carbon Isotopes; D007328:Insulin; D003903:Deuterium; D005947:Glucose