Kraegen E W, James D E, Bennett S P, Chisholm D J
Am J Physiol. 1983 Jul;245(1):E1-7. doi: 10.1152/ajpendo.1983.245.1.E1.
Our aim was to develop the glucose clamp (GC) technique in the conscious rat for assessment of in vivo insulin sensitivity. A 2-h euglycemic GC could be performed in chronically cannulated rats using 625 microliter blood. Overnight-fasted rats were infused with porcine insulin (1.67 mU . kg-1 . h-1). Insulin levels of 41 +/- 2 (SE) mU/liter were produced in rats aged 91 +/- 4 days with a 60- to 120-min glucose infusion rate (GIR60-120) of 10.6 +/- 0.6 mg . kg-1 . min-1 (n = 9) during euglycemia. GIR60-120 was significantly (P less than 0.025) reduced in rats aged greater than 130 days (mean, 169 +/- 16 days) to 7.7 +/- 1.2 mg . kg-1 . min-1 (n = 7). Metabolic clearance rate of porcine insulin (46 +/- 3 ml . kg-1 . min-1) and GIR60-120 compared with plateau plasma insulin levels are higher than values reported in humans. The latter may be due to suppression of a higher basal hepatic glucose production or increased potency of porcine compared with native insulin. We conclude that the GC can be accomplished in the rat. When combined with tracer administration and subsequent killing, it should provide a quantitative in vivo measurement of insulin sensitivity in individual tissues.
我们的目的是在清醒大鼠中开发葡萄糖钳夹（GC）技术，以评估体内胰岛素敏感性。使用625微升血液，可在长期插管的大鼠中进行2小时的正常血糖GC。对过夜禁食的大鼠输注猪胰岛素（1.67 mU·kg-1·h-1）。在血糖正常期间，91±4日龄的大鼠胰岛素水平达到41±2（SE）mU/升，60至120分钟的葡萄糖输注速率（GIR60-120）为10.6±0.6 mg·kg-1·min-1（n = 9）。在大于130日龄（平均169±16日龄）的大鼠中，GIR60-120显著降低（P<0.025）至7.7±1.2 mg·kg-1·min-1（n = 7）。与平台期血浆胰岛素水平相比，猪胰岛素的代谢清除率（46±3 ml·kg-1·min-1）和GIR60-120高于人类报告的值。后者可能是由于基础肝葡萄糖生成的更高抑制或与天然胰岛素相比猪胰岛素效力增加。我们得出结论，GC可在大鼠中完成。当与示踪剂给药和随后的处死相结合时，它应能对个体组织中的胰岛素敏感性进行定量的体内测量。
