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Enteroglucagon and Oxyntomodulin

المؤلف:  Norman, A. W., & Henry, H. L.

المصدر:  Hormones

الجزء والصفحة:  3rd edition , p160-161

2026-07-19

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The topics of enteroglucagon and oxyntomodulin are covered in Chapter 6. The same proglucagon (160 amino acids) in the pancreas secretes the classical 29 amino acid pancreatic glucagon. However, in the intestine it secretes the 69 amino acid glicentin that includes the 29 amino acid sequence of pancreatic glucagon; see Figure1. Enteroglucagon is biosynthesized in the intestinal mucosal L cells of the ileum and colon. It has been postulated to be a trophic factor for the intestinal mucosa.

Fig1. Insulin binding to its membrane receptor results in the translocation of the GLUT4 transport protein from its intracellular storage sites to the plasma membrane. A GLUT4-enhanced green fluorescent protein construct was transfected into differentiated 3T3L1 adipocytes. They were then incubated in the absence (A) or presence (B) of insulin for 30 minutes. Next the cells were fixed and the location of the GLUT4-labeled green fluorescent protein determined by confocal fluorescent microscopy. This figure was provided by R. T. Watson, M. Kanzaki, & J. E. Pessin, Regulated membrane trafficking of the insulin-responsive glucose transporter 4 in adipocytes. Endocrine Reviews 25(2): 177–204 (2004).

Oxyntomodulin is a 37 amino acid peptide that is produced by the stomach’s fundic cells (also known as oxyntic cells) that, like parietal cells, secrete gastric acid. The oxyntomodulin 37 amino acid peptide includes the exact amino acid sequence of pancreatic glucagon. The oxyntomodulin is also found in intestinal and colon cells. Oxyntomodulin and peptide tyrosine–tyrosine (PYY) are secreted from intestinal enteroendocrine cells in response to a meal. These circulating hormones are considered to be satiety signals, as they have been found to decrease food intake, body weight, and adiposity in rodents. It has been proposed that the effects on energy homeostasis are mediated by the brainstem and hypothalamus.