Endogenous somatostatin-28 modulates postprandial insulin secretion. Immunoneutralization studies in baboons.

Published

Journal Article

Somatostatin-28 (S-28), secreted into the circulation from enterocytes after food, and S-14, released mainly from gastric and pancreatic D cells and enteric neurons, inhibit peripheral cellular functions. We hypothesized that S-28 is a humoral regulator of pancreatic B cell function during nutrient absorption. Consistent with this postulate, we observed in baboons a two to threefold increase in portal and peripheral levels of S-28 after meals, with minimal changes in S-14. We attempted to demonstrate a hormonal effect of these peptides by measuring their concentrations before and after infusing a somatostatin-specific monoclonal antibody (mAb) into baboons and comparing glucose, insulin, and glucagon-like peptide-1 levels before and for 4 h after intragastric nutrients during a control study and on 2 d after mAb administration (days 1 and 2). Basal growth hormone (GH) and glucagon levels and parameters of insulin and glucose kinetics were also measured. During immunoneutralization, we found that (a) postprandial insulin levels were elevated on days 1 and 2; (b) GH levels rose immediately and were sustained for 28 h, while glucagon fell; (c) basal insulin levels were unchanged on day 1 but were increased two to threefold on day 2, coincident with decreased insulin sensitivity; and (d) plasma glucose concentrations were similar to control values. We attribute the eventual rise in fasting levels of insulin to its enhanced secretion in compensation for the heightened insulin resistance from increased GH action. Based on the elevated postmeal insulin levels after mAb administration, we conclude that S-28 participates in the enteroinsular axis as a decretin to regulate postprandial insulin secretion.

Full Text

Duke Authors

Cited Authors

  • Ensinck, JW; Vogel, RE; Laschansky, EC; Koerker, DJ; Prigeon, RL; Kahn, SE; D'Alessio, DA

Published Date

  • November 1, 1997

Published In

Volume / Issue

  • 100 / 9

Start / End Page

  • 2295 - 2302

PubMed ID

  • 9410907

Pubmed Central ID

  • 9410907

International Standard Serial Number (ISSN)

  • 0021-9738

Digital Object Identifier (DOI)

  • 10.1172/JCI119767

Language

  • eng

Conference Location

  • United States