Type I Diabetes is Characterized by Insulin Resistance Not Only with Regard to Glucose, but also to Lipid and Aminoacid Metabolism*

Resistance to the metabolic effects of insulin has been reported with regard to glucose disposal in type I diabetic patients (IDDM) even when they were euglycemic. Our aim was to study glucose, lipid, and aminoacid metabolism during glucose clamping at multiple levels of insulin in 10 normal (N) and 6 IDDM patients. Blood glucose was maintained constant (4.7 mmol/liter) at three insulin plateaus (160 min each) [42 ± 6 (SD) 89 ± 11, and 1255 ± 185 μU/ml in N and 36 ± 4, 80 ± 13, and 1249 ± 107 MU/liter in IDDM]. Mean glucose disposal was 34 ± 11, 69 ± 10, and 84 ± 22 μmol kg-1 min-1 in N and 16 + 5, 40 ± 18, and 65 ± 27 in IDDM, respectively. Baseline concentrations of blood lactate, pyruvate, alanine, and branched chain aminoacids were 560 ± 130, 36 ± 9, 212 ± 44, and 451 ± 19 μmol/liter, in N and 793 ± 179 (P < 0.05), 45 ± 14, 195 ± 50, and 439 ± 33 in IDDM, respectively. The maximum percent change of lactate during the euglycemic clamp was + 147 ± 23% in N and +75 ± 15% (P < 0.05) in IDDM; that of branc...