Secretion of the incretin hormones glucagon-like peptide-1 and gastric inhibitory polypeptide correlates with insulin secretion in normal man throughout the day
Research output: Contribution to journal › Journal article › Research › peer-review
BACKGROUND: The insulinotropic hormones gastric inhibitory polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), secreted from the K-cells of the upper small intestine and from the L-cells of the lower small intestine, respectively, are thought to be responsible for intestinal stimulation of insulin secretion. If true, their plasma concentrations should parallel the meal-related diurnal changes in plasma insulin concentrations.
METHODS: Using COOH-terminal assays, thought to reflect accurately their rates of secretion, we measured circulating levels of GIP and GLP-1 in six normal subjects for 15 h of a day, during which they ate three mixed meals.
RESULTS: Both GIP and GLP-1 concentrations increased significantly and in parallel with insulin in response to all three meals. The plasma insulin concentrations correlated significantly with both GIP and GLP-1 values throughout the study period (correlation coefficients, 0.49 +/- 0.07 and 0.56 +/- 0.05; p < 0.001).
CONCLUSIONS: These results support the notion that GLP-1 and GIP are important incretin hormones.
|Book series||Scandinavian Journal of Gastroenterology|
|Number of pages||6|
|Publication status||Published - Jul 1996|
- Adult, Circadian Rhythm, Female, Gastric Inhibitory Polypeptide/secretion, Gastrointestinal Hormones/secretion, Glucagon/secretion, Glucagon-Like Peptide 1, Glucagon-Like Peptides, Humans, Insulin/secretion, Intestine, Small/secretion, Male, Peptide Fragments/secretion