gastrin

Last reviewed 07/2021

Gastrin is a gastrointestinal hormone secreted by G cells in the gastric antrum. It acts on the fundus of the stomach to stimulate:

  • mucosal growth
  • gastric acid secretion:
    • negative feedback regulation ensures that acidic gastric contents inhibit further gastrin production
    • note that acetylcholine, histamine, gastrin and calcium all stimulate parietal cell acid secretion
    • increased vagal activity stimulates acid production

Stimulants of gastrin secretion include:

  • peptides and amino acids in the stomach lumen
  • gastric distension results in vagal stimulation and some gastrin secretion
  • massive small bowel resection is sometimes associated with hypergastrinaemia