The hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are secreted postprandially from intestinal K- and L-cells, respectively. As incretins, these hormones stimulate insulin secretion from the pancreatic β-cell, and have independently been implicated in the control of food intake and lipid metabolism. Whilst the enteroendocrine cells producing GIP and GLP-1 are therefore attractive targets for the treatment of diabetes and obesity, our understanding of their physiology is fairly limited. The mechanisms employed to sense the arrival of carbohydrate, fat and protein in the gut lumen have been investigated using organ perfusion techniques, primary epithelial cultures and cell line models. The recent development of mice with fluorescently labeled GIP or GLP-1-expressing cells is now enabling the use of single cell techniques to investigate stimulus-secretion coupling mechanisms. This review will focus on the current knowledge of the molecular machinery underlying nutrient sensing within K- and L-cells.

中文翻译：

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肠促胰素分泌细胞检测营养的分子机制

激素葡萄糖依赖性促胰岛素多肽 (GIP) 和胰高血糖素样肽-1 (GLP-1) 分别在餐后从肠道 K 细胞和 L 细胞分泌。作为肠促胰素，这些激素刺激胰腺 β 细胞分泌胰岛素，并独立地参与控制食物摄入和脂质代谢。虽然产生 GIP 和 GLP-1 的肠内分泌细胞因此是治疗糖尿病和肥胖症的有吸引力的目标，但我们对其生理学的了解相当有限。已经使用器官灌注技术、原代上皮培养物和细胞系模型研究了用于感知碳水化合物、脂肪和蛋白质到达肠腔的机制。最近开发的带有荧光标记的 GIP 或 GLP-1 表达细胞的小鼠现在可以使用单细胞技术来研究刺激-分泌耦合机制。本综述将重点介绍 K 细胞和 L 细胞内营养感应的分子机制的当前知识。