Dietary regulation of glucose-dependent insulinotropic peptide (GIP) gene expression in rat small intestine.

Journal Article

The hormone, glucose-dependent insulinotropic peptide (GIP), is an important incretin regulator of the gastrointestinal tract. To investigate whether diet is important for the control of GIP gene expression in the small intestine, GIP messenger RNA (mRNA) levels were measured in rats during fasting and after glucose or fat administration. Ribonuclease protection analyses revealed that glucose and fat administration increased GIP mRNA levels by 4-fold and 2.5-fold, respectively, compared with the control, and that prolonged fasting decreased GIP mRNA levels to 44% of those of control animals. Glucose infusion increased plasma GIP levels and tended to stimulate an increase in the GIP hormone concentration in the mucosa of the small intestine. Administration of fat also stimulated an increase of plasma GIP levels but did not modify tissue GIP concentrations. Prolonged fasting tended to decrease plasma GIP levels, although GIP tissue concentrations did not change. These data suggest that dietary glucose or fat stimulates GIP synthesis and secretion, and that food deprivation causes a decrease in GIP synthesis and secretion. This regulation involves changes at the pretranslational level and is reflected by modifications of GIP mRNA expression.

Full Text

Duke Authors

Cited Authors

  • Higashimoto, Y; Opara, EC; Liddle, RA

Published Date

  • February 1995

Published In

Volume / Issue

  • 110 / 2

Start / End Page

  • 207 - 214

PubMed ID

  • 7599968

International Standard Serial Number (ISSN)

  • 1367-8280

Language

  • eng

Conference Location

  • United States