Quon M J, Cochran C, Taylor S I, Eastman R C
Diabetes Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
Diabetes Res. 1994;25(4):139-49.
Estimates of in vivo insulin sensitivity (S1) can be derived from minimal model analysis of a frequently sampled intravenous glucose tolerance test (FSIVGTT). Modification of the FSIVGTT by administration of tolbutamide improves the correlation between S1 and more traditional glucose clamp measurements. Recently, a modified FSIVGTT using insulin infusion (instead of tolbutamide) has been described. This modification may be useful for studying subjects with poor insulin secretion. We directly compare the standard FSIVGTT with the insulin modified FSIVGTT in ten normal subjects (age 29 +/- 2 yr, BMI 22.5 +/- 1.2 kg/m2). Each subject received both tests. The order of the studies was randomized and the interval between paired studies was approximately one week. After an overnight fast, glucose (0.3 g/kg) was infused from time 0 to 2 min. For the modified FSIVGTT, insulin (4 mUkg-1.min-1) was infused from time 20 to 25 min. None of the subjects became hypoglycaemic after insulin infusion. Paired t-test analysis did not reveal significant differences between the two protocols for any of the minimal model parameters. The standard FSIVGTT gave estimates for S1 of 5.63 +/- 1.32 x 10(-4) min-1 per microU/ml while the insulin modified FSIVGTT gave estimates for S1 of 5.11 +/- 0.83 x 10(-4) min-1 per microU/ml. However, the fractional standard deviation for S1 was significantly smaller with the insulin modified protocol (3.6 +/- 1.0 vs. 22.2 +/- 9.0, p < 0.037). Thus, under our experimental conditions, insulin infusion during FSIVGTT appears to improve the precision of minimal model estimation of S1 in normal subjects.
体内胰岛素敏感性（S1）的估计值可通过对频繁采样的静脉葡萄糖耐量试验（FSIVGTT）进行最小模型分析得出。给予甲苯磺丁脲对FSIVGTT进行改良，可提高S1与更传统的葡萄糖钳夹测量值之间的相关性。最近，有人描述了一种使用胰岛素输注（而非甲苯磺丁脲）的改良FSIVGTT。这种改良可能有助于研究胰岛素分泌不良的受试者。我们在10名正常受试者（年龄29±2岁，体重指数22.5±1.2kg/m2）中直接比较了标准FSIVGTT与胰岛素改良FSIVGTT。每位受试者都接受了两种测试。研究顺序是随机的，配对研究之间的间隔约为一周。过夜禁食后，从0至2分钟输注葡萄糖（0.3g/kg）。对于改良FSIVGTT，从20至25分钟输注胰岛素（4mUkg-1.min-1）。胰岛素输注后，没有受试者出现低血糖。配对t检验分析未发现两种方案在任何最小模型参数上有显著差异。标准FSIVGTT得出的S1估计值为5.63±1.32×10-4min-1/每微单位/毫升，而胰岛素改良FSIVGTT得出的S1估计值为5.11±0.83×10-4min-1/每微单位/毫升。然而，胰岛素改良方案中S1的分数标准差显著更小（3.6±1.0对22.2±9.0，p<0.037）。因此，在我们的实验条件下，FSIVGTT期间输注胰岛素似乎提高了正常受试者中S1最小模型估计的精度。
