Weick B G, Ritter S
Physiol Behav. 1986 Oct;38(4):531-6. doi: 10.1016/0031-9384(86)90421-x.
Plasma insulin and glucose concentrations were measured in rats by remote blood sampling techniques 5 and 25 min after the start of a continuous intraportal glucagon infusion (0.33, 1.0, 3.3, 10 and 33 micrograms/kg/min). Plasma insulin levels were elevated in a dose-related fashion by glucagon, with the highest dose producing a 23-fold increase above control levels. In contrast, the glycemic effect of glucagon was not dose-related. Glucagon-induced hyperglycemia was similar for all glucagon doses, despite the fact that a glucagon dose range spanning two orders of magnitude was used. In a second experiment, plasma glucose and insulin were measured as described above at two glucagon infusion rates (1 and 10 micrograms/kg/min), but the animals were allowed to eat during the infusion. Results showed that the effects of glucagon infusions on plasma insulin and glucose were additive with the normal prandial changes in these substances. Finally, food intake was inversely related to insulin level and dissociated from the hyperglycemia during glucagon infusion. These results show that exogenous glucagon provides a potent stimulus for insulin release in the rat both in the presence and in the absence of food. Furthermore, these results in combination with other data suggest that glucagon-induced hyperinsulinemia merits further investigation as one possible determinant of glucagon satiety in the rat.
通过远程采血技术在大鼠持续门静脉内输注胰高血糖素（0.33、1.0、3.3、10和33微克/千克/分钟）开始后5分钟和25分钟测量血浆胰岛素和葡萄糖浓度。胰高血糖素使血浆胰岛素水平呈剂量相关方式升高，最高剂量使胰岛素水平比对照水平增加23倍。相比之下，胰高血糖素的血糖效应与剂量无关。尽管使用了跨越两个数量级的胰高血糖素剂量范围，但所有胰高血糖素剂量引起的高血糖症相似。在第二项实验中，按照上述方法在两个胰高血糖素输注速率（1和10微克/千克/分钟）下测量血浆葡萄糖和胰岛素，但动物在输注期间允许进食。结果表明，胰高血糖素输注对血浆胰岛素和葡萄糖的影响与这些物质正常的餐时变化具有相加性。最后，食物摄入量与胰岛素水平呈负相关，并且在胰高血糖素输注期间与高血糖症无关。这些结果表明，无论有无食物，外源性胰高血糖素均可为大鼠胰岛素释放提供强大刺激。此外，这些结果与其他数据表明，胰高血糖素诱导的高胰岛素血症作为大鼠胰高血糖素饱腹感的一个可能决定因素值得进一步研究。
