Gastrin
Overview[edit | edit source]
Gastrin is a peptide hormone that plays a crucial role in the regulation of gastric acid secretion and the maintenance of the gastric mucosa. It is primarily produced by G-cells located in the antrum of the stomach, the duodenum, and the pancreas.
Structure and Synthesis[edit | edit source]
Gastrin is synthesized as a preprohormone, which is then cleaved to form the active hormone. The most common forms of gastrin are gastrin-17 and gastrin-34, named for the number of amino acids they contain. The synthesis of gastrin is stimulated by the presence of food in the stomach, particularly proteins, and by the vagal nerve stimulation.
Mechanism of Action[edit | edit source]
Gastrin exerts its effects by binding to the cholecystokinin B receptor (CCK-B receptor) on the parietal cells of the stomach lining. This binding stimulates the secretion of hydrochloric acid (HCl) by the parietal cells, which is essential for the digestion of food and the absorption of nutrients. Gastrin also promotes the growth of the gastric mucosa and increases gastric motility.
Regulation of Gastrin Secretion[edit | edit source]
The secretion of gastrin is tightly regulated by several factors:
- Stimulation: Gastrin release is stimulated by the presence of partially digested proteins in the stomach, gastric distension, and vagal stimulation via the release of gastrin-releasing peptide (GRP).
- Inhibition: Gastrin secretion is inhibited by the presence of somatostatin, a hormone produced by D-cells in the stomach and duodenum, and by the presence of acid in the stomach, which provides negative feedback to prevent excessive acid production.
Clinical Significance[edit | edit source]
Abnormal levels of gastrin can lead to various clinical conditions:
- Hypergastrinemia: Excessive levels of gastrin can result in conditions such as Zollinger-Ellison syndrome, where gastrin-secreting tumors (gastrinomas) cause excessive gastric acid production, leading to recurrent peptic ulcers.
- Hypogastrinemia: Low levels of gastrin can be associated with conditions such as atrophic gastritis, where the loss of gastric mucosa leads to reduced acid secretion.
Related Pages[edit | edit source]
Search WikiMD
Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD
|
WikiMD's Wellness Encyclopedia |
| Let Food Be Thy Medicine Medicine Thy Food - Hippocrates |
Translate this page: - East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
தமிழ்,
తెలుగు,
Urdu,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
বাংলা
European
español,
Deutsch,
français,
Greek,
português do Brasil,
polski,
română,
русский,
Nederlands,
norsk,
svenska,
suomi,
Italian
Middle Eastern & African
عربى,
Turkish,
Persian,
Hebrew,
Afrikaans,
isiZulu,
Kiswahili,
Other
Bulgarian,
Hungarian,
Czech,
Swedish,
മലയാളം,
मराठी,
ਪੰਜਾਬੀ,
ગુજરાતી,
Portuguese,
Ukrainian
Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates, categories Wikipedia, licensed under CC BY SA or similar.
Contributors: Prab R. Tumpati, MD
