Most impoant site for gastrin-producing cells

Gastrin is produced by cells called G cells in the antral poion of the gastric mucosa. G cells are flask-shaped, with a broad base containing many gastrin granules and a narrow apex that reaches the mucosal surface. Microvilli project from the apical end into the lumen. Receptors mediating gastrin responses to changes in gastric contents are present on the microvilli. Other cells in the gastrointestinal tract that secrete hormones have a similar morphology.Ref: Ganong&;s review of medical physiology 23rd edition Page no; 443