Secretin

Secretin is a gastrointestinal peptide hormone in higher mammals. In humans, secretin stops the production of stomach acid and causes the pancreas to make sodium bicarbonate -rich secretion. It belongs to the glucagon family of peptide hormones.

Its precursor is the so-called Prosekretin. It was - after the adrenaline - the second hormone that was discovered. William Bayliss and Ernest Starling found in 1902 in experiments on digestion its function and defined out the 1905 term hormone.

Made it in S cells of the duodenum. The stimulus for secretion is a low pH ( below 4.5 ) of the chyme in the duodenum.

Target organs and mode of action

Secretin

  • Leads to an increased production of sodium bicarbonate ( NaHCO3) in the pancreas, gallbladder and small intestine
  • {[ not, however, so the gastrinoma ( Zollinger -Ellison syndrome) ] of the healthy stomach } inhibits gastrin secretion and
  • Leads to the contraction of the gallbladder
  • Increases the production of mucins in the gastric mucosal cells, and thus delays the gastric emptying
  • Stimulates the release of insulin and somatostatin.
Human Genome Organisation Eutheria Digital Object Identifier
720677
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