The Insulin Sensitivity Index: Correlation in Dogs Between Values Determined from the Intravenous Glucose Tolerance Test and the Euglycemic Glucose Clamp

摘要: We previously proposed the insulin sensitivity index, S1as an absolute measure of whole body tissue to insulin. S1 is defined, in physiologic range action, as effect augment glucose's ability reduce its own plasma level. This parameter can be determined from frequently sampled intravenous glucose tolerance test (IVGTT) by using a digital computer find coefficients minimal mathematical model kinetics. In present study we compared, normal dogs, S, IVGTT analogous “S1(clamp)” calculated euglycemic clamp (EGC). Fifteen pairs experiments (1 and 1 EGC) were performed on 12 animals. IVGTTs: After injection (0.3 g/kg), frequent blood samples taken over subsequent 3 h. KG ranged 1.7 4.7 %/min, integrated 0.4 5.9 (μU/ml) min for 0–60 min. varied ninefold 1.0 9.1 × 10−4 (min−1)/μU/ml), with mean 4.3 ± 0.7 10−4. Fractional disappearance rate independent (p1) was 0.5 %/min. EGCs: Low-rate infusion (8 mU/min 150 min) elevated (INS) 15 4 43 10 μU/ml. Glucose infused (GINF) at 119 20 mg/min maintain euglycemia. Moderate (40 mU/min: 151–300 further (to 176 37 μU/ml) requisite 372 36 mg/min). S1(clamp) steady state increase per increment above basal, normalized basal weight [GINF/(Gb BW δINS)]. 3.1 40.5 (dl/kg/min)/μU/ml). The values highly correlated (r = 0.82, P < 0.005). These studies suggest that S1determined useful sensitivity, which capable differentiating sensitivities among population.