Gastroenterology

Gastroenterology

Volume 119, Issue 3, September 2000, Pages 744-755
Gastroenterology

Alimentary Tract
Enteroendocrine localization of GLP-2 receptor expression in humans and rodents,☆☆

https://doi.org/10.1053/gast.2000.16489Get rights and content

Abstract

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.

GASTROENTEROLOGY 2000;119:744-755

Section snippets

Animals

Mice transgenic for the rat GLP-2R complementary DNA (cDNA) under the control of the intestinal fatty acid–binding protein (FABP) promoter14 were generated and propagated in accordance with the guidelines of the Toronto General Hospital Animal Care Committee. These mice were generated to assess the effects on enterocyte biology of targeted expression of the GLP-2R to a localized intestinal epithelial compartment.14 Because FABP–GLP-2R mice express high levels of the translated rat GLP-2R in the

Results

Multiple GLP-1R RNA transcripts have been detected using Northern blotting and GLP-1R–specific cDNA probes10, 24; however, whether the GLP-2R gene also gives rise to multiple transcripts is not currently known. Because messenger RNA (mRNA) transcripts for related members of the glucagon receptor superfamily potentially cross-hybridize with GLP-2R probes, we first ascertained the specificity of Northern blotting for detection of GLP-2R mRNA transcripts. RNA isolated from rat jejunum, lung,

Discussion

Our studies show that GLP-2R expression, as assessed by a combination of Northern blotting, RT-PCR, and immunocytochemistry, is predominantly restricted to the gastrointestinal tract and brain. The observation that GLP-2R–mRNA transcripts are expressed at low levels in the gastrointestinal tract, and detectable only by sensitive techniques such as Northern blotting with polyA+ RNA, RNAse protection assays, or RT-PCR, is in keeping with previous efforts that failed to detect GLP-2 binding in the

Acknowledgements

The authors thank Dr. D. Irwin for technical assistance.

References (46)

  • DJ Drucker et al.

    Regulation of the biological activity of glucagon-like peptide 2 by dipeptidyl peptidase IV

    Nat Biotechnol

    (1997)
  • WT Chance et al.

    Prevention of parenteral nutrition-induced gut hypoplasia by coinfusion of glucagon-like peptide-2

    Am J Physiol

    (1997)
  • DJ Drucker et al.

    Human [Gly2]-GLP-2 reduces the severity of colonic injury in a murine model of experimental colitis

    Am J Physiol

    (1999)
  • RB Scott et al.

    GLP-2 augments the adaptive response to massive intestinal resection in rat

    Am J Physiol

    (1998)
  • LJ Jelinek et al.

    Expression cloning and signaling properties of the rat glucagon receptor

    Science

    (1993)
  • B Thorens

    Expression cloning of the pancreatic β cell receptor for the gluco-incretin hormone glucagon-like peptide 1

    Proc Natl Acad Sci U S A

    (1992)
  • DG Munroe et al.

    Prototypic G protein-coupled receptor for the intestinotrophic factor glucagon-like peptide 2

    Proc Natl Acad Sci U S A

    (1999)
  • B Yusta et al.

    Restricted cellular specificity of GLP-2 action in FABP-GLP-2 receptor transgenic mice

    Gastroenterology

    (1999)
  • D Gajic et al.

    Multiple cis-acting domains mediate basal and adenosine 3',5'-monophosphate-dependent glucagon gene transcription in a mouse neuroendocrine cell line

    Endocrinology

    (1993)
  • DJ Drucker et al.

    Activation of proglucagon gene transcription by protein kinase A in a novel mouse enteroendocrine cell line

    Mol Endocrinol

    (1994)
  • RV Campos et al.

    Divergent tissue-specific and developmental expression of receptors for glucagon and glucagon-like peptide-1 in the mouse

    Endocrinology

    (1994)
  • MB Wheeler et al.

    Functional expression of the rat pancreatic islet glucose-dependent insulinotropic polypeptide receptor: ligand binding and intracellular signaling properties

    Endocrinology

    (1995)
  • M Piechaczyk et al.

    Post-transcriptional regulation of glyceraldehyde-3-phosphate dehydrogenase gene expression in rat tissues

    Nucleic Acids Res

    (1984)
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    Address correspondence to: Daniel Drucker, M.D., Toronto General Hospital, 200 Elizabeth Street, CCRW3-845, Toronto, M5G 2C4, Canada. e-mail: [email protected]; fax: (416) 978-4108.

    ☆☆

    Supported by a Senior Scientist Award (to D.D.) from the Medical Research Council (MRC) of Canada and in part by operating grants from the MRC of Canada and by an Ontario Research and Development Challenge Fund Award. Dr. Drucker is a consultant to NPS Allelix Inc., and GLP-2 is the subject of a licensing agreement between the Toronto General Hospital, University of Toronto, and NPS Allelix Inc.

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