Peptide Database

Glucose-dependent Insulinotropic Polypeptide · Gastric Inhibitory Polypeptide

GIP is a 42-amino-acid incretin hormone secreted by duodenal K-cells in response to fat and carbohydrate ingestion. Like GLP-1, it enhances glucose-dependent insulin secretion. Unlike GLP-1, it also promotes insulin secretion during hypoglycemia, protects β-cells, and at high doses may stimulate glucagon in a glucose-independent manner. The GIP receptor's role in energy homeostasis underlies the efficacy of dual GIP/GLP-1 agonists like tirzepatide.