Collier G R, Greenberg G R, Wolever T M, Jenkins D J
Department of Nutritional Sciences, St. Michael's Hospital, Toronto, Ontario, Canada.
J Clin Endocrinol Metab. 1988 Feb;66(2):323-6. doi: 10.1210/jcem-66-2-323.
Previous studies suggest that the rate of rise of the plasma glucose-dependent insulinotropic peptide (GIP) concentration, rather than the steady state level achieved, may be the stimulus of the increased insulin secretion that occurs when fat is ingested with carbohydrate. To test this hypothesis six normal men were given a 5-g iv bolus dose of glucose 15 min after a carbohydrate meal with or without fat. At the time of the iv glucose injection after the fat-containing meal, the rate of rise of plasma GIP was maximum, but the level was only 40% of the achieved by 30 min. Plasma GIP did not change after the meal without fat. After the fat meal, peak insulin and C-peptide levels in response to iv glucose were 60% greater than those after carbohydrate alone despite similar peak blood glucose levels. The calculated insulin clearance was not altered by the fat meal. We conclude that glucose-stimulated insulin secretion is increased early after fat ingestion, possibly due to a rise in GIP or other incretins.
先前的研究表明，血浆葡萄糖依赖性促胰岛素多肽（GIP）浓度的上升速率，而非所达到的稳态水平，可能是在脂肪与碳水化合物一同摄入时发生的胰岛素分泌增加的刺激因素。为了验证这一假设，六名正常男性在摄入含或不含脂肪的碳水化合物餐后15分钟，静脉注射5克葡萄糖推注剂量。在含脂肪餐之后进行静脉注射葡萄糖时，血浆GIP的上升速率达到最大值，但该水平仅为30分钟时所达到水平的40%。无脂肪餐后血浆GIP没有变化。尽管峰值血糖水平相似，但在含脂肪餐后，静脉注射葡萄糖后胰岛素和C肽的峰值水平比单独摄入碳水化合物后高60%。脂肪餐并未改变计算得出的胰岛素清除率。我们得出结论，在摄入脂肪后早期，葡萄糖刺激的胰岛素分泌增加，这可能是由于GIP或其他肠促胰岛素的升高所致。
