Knapper J M, Heath A, Fletcher J M, Morgan L M, Marks V
School of Biological Sciences, University of Surrey, Guildford, U.K.
Comp Biochem Physiol C Pharmacol Toxicol Endocrinol. 1995 Jul;111(3):445-50. doi: 10.1016/0742-8413(95)00046-1.
Investigation of nutrient stimulation of two gut hormones GIP (glucose dependent insulotropic polypeptide) and GLP-1(7-36)amide (the active truncated form of glucagon-like peptide-1) is made difficult by the differential control of gastric emptying. Direct nutrient infusion into the duodenum was therefore carried out on three female pigs. The infusates consisted of saline (0.85 g or 1.7 g/100 ml); glucose (20 g or 40 g/100 ml); fat (30 g or 60 g/500 ml) and glucose/fat (20 g and 30 g or 40 g and 60 g per 1000 ml). Plasma glucose levels were elevated as expected by glucose or glucose/fat infusions, and they were not affected by the presence of fat in the infusate. Insulin secretion was stimulated in the presence of glucose or glucose/fat. Plasma triacylglycerol was elevated following fat and glucose/fat infusions. The greatest stimulus for GIP secretion was glucose/fat (P < 0.05); fat alone was a poor stimulus for GIP secretion, but glucose was a potent stimulus. GLP-1(7-36)amide was moderately stimulated by glucose and markedly stimulated by fat and glucose/fat infusions (P < 0.05). We conclude that, in pigs, dual nutrient infusion of glucose/fat is a strong stimulus for both GIP and GLP-1(7-36)amide secretion. The hormones therefore have the potential to play an important physiological role, both in the stimulation of insulin secretion and in adipose tissue metabolism in pigs.
胃排空的差异控制使得对两种肠促胰岛素激素——葡萄糖依赖性促胰岛素多肽（GIP）和胰高血糖素样肽-1（7-36）酰胺（胰高血糖素样肽-1的活性截短形式）的营养刺激研究变得困难。因此，对三头雌性猪进行了直接向十二指肠输注营养物质的操作。输注液包括生理盐水（0.85 g或1.7 g/100 ml）；葡萄糖（20 g或40 g/100 ml）；脂肪（30 g或60 g/500 ml）以及葡萄糖/脂肪（每1000 ml含20 g和30 g或40 g和60 g）。正如预期的那样，葡萄糖或葡萄糖/脂肪输注使血浆葡萄糖水平升高，且输注液中脂肪的存在并未对其产生影响。葡萄糖或葡萄糖/脂肪存在时刺激了胰岛素分泌。脂肪和葡萄糖/脂肪输注后血浆三酰甘油升高。对GIP分泌的最大刺激因素是葡萄糖/脂肪（P < 0.05）；单独的脂肪对GIP分泌的刺激作用较弱，但葡萄糖是一种强效刺激因素。葡萄糖对GLP-1（7-36）酰胺有适度刺激作用，脂肪和葡萄糖/脂肪输注则对其有显著刺激作用（P < 0.05）。我们得出结论，在猪中，葡萄糖/脂肪的双重营养输注对GIP和GLP-1（7-36）酰胺的分泌均有强烈刺激作用。因此，这些激素在刺激猪的胰岛素分泌和脂肪组织代谢方面都有可能发挥重要的生理作用。
