Old and New Gut Hormone, Gastrin and Acid Suppressive Therapy.

Gastrin acts physiologically as a gut hormone to stimulate acid secretion after meal and as a cell-growth factor of oxyntic mucosa. Increase in serum gastrin level happens under various conditions including Zollinger-Ellison syndrome, antral G cell hyperplasia, autoimmune gastritis, atrophic gastritis, renal failure, vagotomy, Helicobacter pylori infection and acid suppressive therapy. As acid suppressive therapy causes hypergastrinemia, the association between acid suppressive therapy and gastric neuroendocrine cell tumor (NET) has been discussed during the past 30 years. In this review article, the definition of hypergastrinemia and the related disorders including acid suppressive therapy and gastric NET are discussed.