Glucose-dependent insulinotropic polypeptide and insulin-like immunoreactivity in saliva following sham-fed and swallowed meals

What Was Tested

The paper reports a study of GIP (Gastric Inhibitory Polypeptide), published as a randomized controlled trial.

This study therefore investigated and compared postprandial hormone concentrations in saliva and plasma to determine whether their secretion was influenced by oral food stimuli.

Why It Was Studied

Gastrointestinal peptides, including insulin, glucagon and glucose-dependent insulinotropic polypeptide (GIP) have previously been reported in salivary glands.

On one occasion the meal was chewed and swallowed (swallowed meal), on the other it was chewed and expectorated (sham-fed meal).

Who Took Part

The abstract describes 12 subjects taking part.

PubMed indexes the participants as adults, both men and women.

In a within-subject randomised cross-over comparison of hormone concentrations in plasma and saliva following a mixed meal, 12 subjects were given two 1708 kJ mixed meals.

How the Study Was Run

The researchers set it up as a randomized and crossover study.

Random assignment meant chance, not the researchers, decided who got GIP (Gastric Inhibitory Polypeptide) and who got the comparison, which limits bias.

In the crossover set-up each of the subjects took both GIP (Gastric Inhibitory Polypeptide) and the comparison in turn, acting as their own control.

Salivary and plasma levels of immunoreactive insulin, GIP and glucagon-like peptide-1 (GLP-1), total protein, alpha-amylase, glucose and non-esterified fatty acid were measured before and for 90 min following the meals.

What Was Measured

Gastrointestinal peptides, including insulin, glucagon and glucose-dependent insulinotropic polypeptide (GIP) have previously been reported in salivary glands.

PubMed files the paper under topics including Analysis of Variance, Blood Glucose, Blood Proteins, Fatty Acids, Nonesterified, Gastric Inhibitory Polypeptide, Glucagon and Glucagon-Like Peptide 1.

What This Means in Plain Language

The paper is a randomized and crossover study of GIP (Gastric Inhibitory Polypeptide) in 12 subjects.

With fewer than 40 people, it is a small study, so it is better read as an early signal for further research than as a settled answer.

The publication is from 2003 (The Journal of endocrinology), a journal based in England.

More context: the GIP (Gastric Inhibitory Polypeptide) compound page, all human trials.