Secretin is a hormone that regulates water homeostasis throughout the body and influences the environment of the duodenum by regulating secretions in the stomach, pancreas, and liver. It is a peptide hormone produced in the S cells of the duodenum, which are located in the intestinal glands.[5] In humans, the secretin peptide is encoded by the SCT gene.[6]
Secretin helps regulate the pH of the duodenum by inhibiting the secretion of gastric acid from the parietal cells of the stomach and stimulating the production of bicarbonate from the ductal cells of the pancreas.[7][8] It also stimulates the secretion of bicarbonate and water by cholangiocytes in the bile duct, protecting it from bile acids by controlling the pH and promoting the flow in the duct.[9] Meanwhile, in concert with secretin's actions, the other main hormone simultaneously issued by the duodenum, cholecystokinin (CCK), stimulates the gallbladder to contract, delivering its stored bile.
Prosecretin is a precursor to secretin, which is present in digestion. Secretin is stored in this unusable form, and is activated by gastric acid. This indirectly results in the neutralisation of duodenal pH, thus ensuring no damage is done to the small intestine by the aforementioned acid.[10]
In 2007, secretin was discovered to play a role in osmoregulation by acting on the hypothalamus, pituitary gland, and kidney.[11][12]
- ^ a b c ENSG00000274473 GRCh38: Ensembl release 89: ENSG00000070031, ENSG00000274473 – Ensembl, May 2017
- ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000038580 – Ensembl, May 2017
- ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
- ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
- ^ Häcki WH (September 1980). "Secretin". Clinics in Gastroenterology. 9 (3): 609–632. doi:10.1016/S0300-5089(21)00474-0. PMID 7000396.
- ^ Kopin AS, Wheeler MB, Leiter AB (March 1990). "Secretin: structure of the precursor and tissue distribution of the mRNA". Proceedings of the National Academy of Sciences of the United States of America. 87 (6): 2299–2303. Bibcode:1990PNAS...87.2299K. doi:10.1073/pnas.87.6.2299. JSTOR 2354038. PMC 53674. PMID 2315322.
- ^ Whitmore TE, Holloway JL, Lofton-Day CE, Maurer MF, Chen L, Quinton TJ, et al. (2000). "Human secretin (SCT): gene structure, chromosome location, and distribution of mRNA". Cytogenetics and Cell Genetics. 90 (1–2): 47–52. doi:10.1159/000015658. PMID 11060443. S2CID 12850155.
- ^ Costanzo, Linda S. (2006). Physiology (3rd ed.). Philadelphia, PA: Saunders Elsevier. ISBN 9781416023203. OCLC 62326921.
- ^ Banales JM, Huebert RC, Karlsen T, Strazzabosco M, LaRusso NF, Gores GJ (May 2019). "Cholangiocyte pathobiology". Nature Reviews. Gastroenterology & Hepatology. 16 (5): 269–281. doi:10.1038/s41575-019-0125-y. PMC 6563606. PMID 30850822.
- ^ Gafvelin G, Jörnvall H, Mutt V (September 1990). "Processing of prosecretin: isolation of a secretin precursor from porcine intestine". Proceedings of the National Academy of Sciences of the United States of America. 87 (17): 6781–6785. Bibcode:1990PNAS...87.6781G. doi:10.1073/pnas.87.17.6781. PMC 54621. PMID 2395872.
- ^ Chu JY, Chung SC, Lam AK, Tam S, Chung SK, Chow BK (April 2007). "Phenotypes developed in secretin receptor-null mice indicated a role for secretin in regulating renal water reabsorption". Molecular and Cellular Biology. 27 (7): 2499–2511. doi:10.1128/MCB.01088-06. PMC 1899889. PMID 17283064.
- ^ Chu JY, Lee LT, Lai CH, Vaudry H, Chan YS, Yung WH, Chow BK (September 2009). "Secretin as a neurohypophysial factor regulating body water homeostasis". Proceedings of the National Academy of Sciences of the United States of America. 106 (37): 15961–15966. Bibcode:2009PNAS..10615961C. doi:10.1073/pnas.0903695106. JSTOR 40484830. PMC 2747226. PMID 19805236.