BACKGROUND & AIMS: Glucagon-like peptide (GLP)-2, a product of the proglucagon gene, is expressed in enteroendocrine cells of the small and large intestine and is trophic to the gastrointestinal mucosa. GLP-2 also inhibits gastric acid secretion and emptying and up-regulates intestinal hexose transport. GLP-2 acts via binding to a single G protein-coupled GLP-2 receptor (GLP-2R), but the cellular targets for the diverse actions of GLP-2 remain unknown. METHODS: GLP-2R expression in rodent and human tissues was examined using a combination of Northern blotting, reverse-transcription polymerase chain reaction (RT-PCR), and immunocytochemistry. RESULTS: A single major GLP-2R messenger RNA transcript was detected by Northern blot analysis in rodent stomach, duodenum, jejunum, ileum, and colon, but not in rodent esophagus. GLP-2R expression was also detected by RT-PCR in RNA from the hypothalamus, brain stem, and lung. Immunocytochemical localization of human GLP-2R expression using specific antisera detected GLP-2R immunopositivity in subsets of endocrine cell populations in the epithelium of the stomach and both the small and large bowel. CONCLUSIONS: These findings suggest that enteroendocrine-derived GLP-2 acts directly on endocrine cells to induce one or more downstream mediators of GLP-2 action in the gastrointestinal tract.
BACKGROUND & AIMS:Glucagon-like peptide (GLP)-2, a product of the proglucagon gene, is expressed in enteroendocrine cells of the small and large intestine and is trophic to the gastrointestinal mucosa. GLP-2 also inhibits gastric acid secretion and emptying and up-regulates intestinal hexose transport. GLP-2 acts via binding to a single G protein-coupled GLP-2 receptor (GLP-2R), but the cellular targets for the diverse actions of GLP-2 remain unknown. METHODS:GLP-2R expression in rodent and human tissues was examined using a combination of Northern blotting, reverse-transcription polymerase chain reaction (RT-PCR), and immunocytochemistry. RESULTS: A single major GLP-2R messenger RNA transcript was detected by Northern blot analysis in rodent stomach, duodenum, jejunum, ileum, and colon, but not in rodent esophagus. GLP-2R expression was also detected by RT-PCR in RNA from the hypothalamus, brain stem, and lung. Immunocytochemical localization of humanGLP-2R expression using specific antisera detected GLP-2R immunopositivity in subsets of endocrine cell populations in the epithelium of the stomach and both the small and large bowel. CONCLUSIONS: These findings suggest that enteroendocrine-derived GLP-2 acts directly on endocrine cells to induce one or more downstream mediators of GLP-2 action in the gastrointestinal tract.
Authors: Rhonda D Wideman; Irene L Y Yu; Travis D Webber; C Bruce Verchere; James D Johnson; Anthony T Cheung; Timothy J Kieffer Journal: Proc Natl Acad Sci U S A Date: 2006-08-28 Impact factor: 11.205
Authors: Amosy E M'Koma; Paul E Wise; Roberta L Muldoon; David A Schwartz; Mary K Washington; Alan J Herline Journal: Int J Colorectal Dis Date: 2007-06-19 Impact factor: 2.571