Also known as ChiRhoStim · human secretin
The first hormone ever discovered — the 1902 gut peptide that coined the word "hormone"; today a diagnostic agent for the pancreas.
Research refreshed
Secretin is a 27-amino-acid hormone of the upper small intestine that signals the pancreas and bile ducts to release bicarbonate-rich fluid, neutralizing stomach acid as it enters the duodenum. Its historical importance is hard to overstate: discovered by Bayliss and Starling in 1902, it was the first chemical messenger ever identified, and Starling coined the very word "hormone" to describe it. Synthetic human secretin (ChiRhoStim) is used today mainly as a diagnostic stimulant in pancreatic-function and imaging tests.
Secretin is where endocrinology begins. In 1902 William Bayliss and Ernest Starling showed that acid in the small intestine triggers pancreatic secretion even when all the nerves are cut — proof that a blood-borne chemical, not a nerve, carried the message. Starling later named this new class of messengers "hormones," from the Greek for "to set in motion." Secretin is therefore both a working hormone and the founding object of the entire field, which is reason enough for it to anchor this category historically.
Physiologically it is a bicarbonate hormone. Released by S-cells of the duodenum when acidic chyme arrives, secretin drives the pancreas and bile ducts to pour out an alkaline, bicarbonate-rich fluid that protects the intestinal lining and creates the neutral pH that digestive enzymes need. It belongs to the secretin/glucagon/VIP superfamily, sharing a structural template with several other gut and metabolic hormones in this catalog.
Its modern role is diagnostic rather than therapeutic. Synthetic human secretin is given to stimulate pancreatic output during function testing and secretin-enhanced MRCP imaging, and to provoke gastrin release in the diagnosis of gastrinoma (Zollinger–Ellison syndrome). A once-fashionable hypothesis that secretin might treat autism was tested in controlled trials and clearly failed — a useful, honest footnote to a hormone whose real value is as a precise diagnostic tool.
Agonist at the secretin receptor (a class B GPCR) on pancreatic duct and biliary cells, raising cAMP and stimulating secretion of water and bicarbonate. It also modestly inhibits gastric acid and gastric emptying.
Behind every vial of Secretin is the same exacting pipeline every research peptide runs — but the chemistry plays out differently for this molecule. Here is how Secretin, specifically, is brought into being.
On paper, Secretin weighs in at roughly 3,039.4 daltons. Before a single bond is made, the target sequence, salt form, and purity threshold are written down as the contract the finished material must meet.
Secretin's chain is short but unusual — it carries non-natural residues that help it resist enzymatic breakdown, but demand specialized, costlier building blocks and careful coupling on the synthesizer.
The crude mixture — Secretin plus its deletions and side products — is then separated on preparative HPLC, and where the cut is taken decides the difference between a genuinely pure peptide and a barely-passable one.
A real batch of Secretin proves itself: identity confirmed by mass spectrometry against its ~3,039.4 Da, purity read directly off an analytical HPLC trace, water and counterion content measured. That batch-specific certificate of analysis is the only honest way to know what is actually in a vial of Secretin — and a short, cold, accountable chain of custody is how that purity survives the trip to your bench.
A 27-residue C-terminal-amide peptide of the secretin/glucagon/VIP family, made by solid-phase synthesis with a terminal amidation step. The meaningful modern change is provenance rather than chemistry: the clinical agent (synthetic human secretin, ChiRhoStim) replaced earlier porcine material extracted from animal tissue. That shift — from variable animal extract to a defined, sequence-verified synthetic product with a certificate of analysis — is the core quality story for older hormone peptides and exactly the transparency this catalog tracks.
Don't judge a vial by its cake. A fluffy, good-looking lyophilized powder reflects bulking agents and freeze-drying parameters — not purity. Insist on a batch-specific certificate of analysis.
Recent clinical trials and publications mentioning Secretin, pulled automatically from ClinicalTrials.gov and PubMed and refreshed daily. Listings are unfiltered search results, not curated endorsements.
It signals the pancreas and bile ducts to release bicarbonate-rich fluid that neutralizes stomach acid entering the small intestine. It is released by the duodenum in response to acid.
It was the first hormone ever discovered (1902), and its discovery prompted Ernest Starling to coin the word "hormone." It effectively founded the science of endocrinology.
Mainly diagnosis — stimulating pancreatic secretion for function tests and MRCP imaging, and provoking gastrin release to diagnose gastrinoma. A past idea that it could treat autism was tested and disproven.
No — this is a research and educational reference, not dosing guidance.
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