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Updated: Sep 11, 2026

Mixed Primary Cultures of Murine Small Intestine Intended for the Study of Gut Hormone Secretion and Live Cell Imaging of Enteroendocrine Cells
09:16

Mixed Primary Cultures of Murine Small Intestine Intended for the Study of Gut Hormone Secretion and Live Cell Imaging of Enteroendocrine Cells

Published on: April 20, 2017

Ontogeny of glucagon messenger RNA and encoded precursor in the rat intestine

S L Jin1, M A Hynes, P K Lund

  • 1Department of Physiology, School of Medicine, University of North Carolina, Chapel Hill 27599-7545.

Regulatory Peptides
|July 30, 1990
PubMed

Insights

Intestinal proglucagon gene expression begins around day 14 of fetal development in rats. A significant increase in L cell numbers between days 17 and 18 correlates with rising proglucagon mRNA levels.

Area of Science:

  • Developmental biology
  • Molecular endocrinology
  • Gastrointestinal physiology

Background:

  • Proglucagon is a key hormone precursor synthesized in intestinal L cells.
  • Understanding the regulation of proglucagon during development is crucial for metabolic research.

Purpose of the Study:

  • To investigate the ontogeny of proglucagon mRNA and its precursor in the developing rat intestine.
  • To identify the onset and developmental trajectory of intestinal proglucagon gene expression.

Main Methods:

  • Immunocytochemistry to detect proglucagon antigenic determinants.
  • In situ hybridization histochemistry to quantify proglucagon mRNA.
  • Analysis of L cell density during fetal gestation.

Main Results:

  • Proglucagon expression and mRNA translation were first detected at day 14 of fetal gestation (E14).
  • A significant 10-fold increase in intestinal L cell density occurred between E17 and E18.
  • Proglucagon mRNA abundance increased 8-fold between E17 and E18, correlating with L cell proliferation.

Conclusions:

  • Intestinal proglucagon gene expression initiates around E14 in rats.
  • The surge in proglucagon mRNA between E17-E18 is primarily attributed to an increase in L cell numbers.
  • This study provides insights into the developmental regulation of proglucagon in the gut.

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