Definition and research guide
This page combines a MeSH definition, publication statistics and selected research abstracts. It is a starting point for reading the literature, not a medical textbook or a systematic evidence review.
Content available: 4 complete abstracts (727 words), 10 references. Full article text is not stored or reproduced here; follow the PMID, DOI or PMC links to read the original sources and their access terms.
Definition
A peptide hormone of about 27 amino acids from the duodenal mucosa that activates pancreatic secretion and lowers the blood sugar level. (USAN and the USP Dictionary of Drug Names, 1994, p597)
Definition: NLM Medical Subject Headings (MeSH) scope note (Public domain (U.S. National Library of Medicine); attribution requested). View the MeSH record.
Also known as: Secretin, Pig; Pig Secretin; Secretin Pentacetate, Pig; Pig Secretin Pentacetate; Secretin Sulfate, Pig; Pig Secretin Sulfate; Secretin Maleate, Pig; Pig Secretin Maleate.
Where it fits in the MeSH classification
- Broader topics
- Gastrointestinal Hormones; Peptide Hormones; Neuropeptides
Research landscape
PubMed indexes 6,256 records tagged with the MeSH heading “Secretin” (counts retrieved 2026-10-31). 100 of them (1.6%) were published from 2020 onward, and the busiest period so far is through 1999 with 5,338 records.
Reviews account for 510 records (8.2%) and meta-analyses for 5. Randomized controlled trials number 81 (1.3%) as a share of all records on the topic. Randomized trials make up only a small share of this literature, so much of what is known comes from laboratory, observational or descriptive work.
Show the data
| Period | Records |
|---|---|
| through 1999 | 5,338 |
| 2000-2009 | 552 |
| 2010-2019 | 266 |
| 2020 onward | 100 |
Publication-type chart data
| Type | Records | Share |
|---|---|---|
| Reviews | 510 | 8.2% |
| Meta-analyses | 5 | 0.1% |
| Randomized controlled trials | 81 | 1.3% |
Method: PubMed query "Secretin"[MeSH Terms] with publication-type and date filters, retrieved 2026-10-31.
Reading the evidence in drugs and chemicals
Studies of a chemical or drug can answer very different questions: what it is and how it behaves in cells and animals, how the body handles it, and whether it changes outcomes in people. Laboratory and animal findings often do not carry over to patients, and observational studies of exposures are confounded by who uses a substance and why. Nothing on this page is a recommendation to use, avoid, start or stop any substance or medicine; talk to a qualified clinician or pharmacist about your own situation. Check the dose, the species, the comparison group and whether a patient-relevant outcome was measured.
Evidence from open-access studies
These open-access studies come from PubMed’s best-match results for this heading (papers whose main topic it is), ranked here by citation count, with one recent addition. Each abstract is reproduced in full under its recorded open licence so that you can read the authors’ own words. They illustrate the literature; they are not a systematic summary of it. Citation counts measure attention, not reliability or clinical benefit.
| Study / authors | Year | Source label / design | Europe PMC citations | Licence / source |
|---|---|---|---|---|
| Structure of a type IV pilus machinery in the open and closed state | 2015 | Research article Design not recorded in structured metadata | 104 | cc by PMID 25997099 · DOI · PMC4463427 |
| Evolution of secretin family GPCR members in the metazoa | 2006 | Research article Design not recorded in structured metadata | 92 | cc by PMID 17166275 · DOI · PMC1764030 |
| Multiplexed analysis of the secretin-like GPCR-RAMP interactome | 2019 | Research article Design not recorded in structured metadata | 71 | cc by PMID 31555726 · DOI · PMC6750928 |
| Secretin targets interstitial cells of Cajal to regulate intestinal contractions | 2025 | Research article Design not recorded in structured metadata | 2 | cc by PMID 41198902 · DOI · PMC12678811 |
Structure of a type IV pilus machinery in the open and closed state [1]
Abstract reading summary — source excerpts
- Opening excerpt
- Proteins of the secretin family form large macromolecular complexes, which assemble in the outer membrane of Gram-negative bacteria.
- Closing excerpt
- Furthermore, we determine the structure of the assembled pilus.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (108 words)
Proteins of the secretin family form large macromolecular complexes, which assemble in the outer membrane of Gram-negative bacteria. Secretins are major components of type II and III secretion systems and are linked to extrusion of type IV pili (T4P) and to DNA uptake. By electron cryo-tomography of whole Thermus thermophilus cells, we determined the in situ structure of a T4P molecular machine in the open and the closed state. Comparison reveals a major conformational change whereby the N-terminal domains of the central secretin PilQ shift by ~30 Å, and two periplasmic gates open to make way for pilus extrusion. Furthermore, we determine the structure of the assembled pilus.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 25997099 · DOI · PMC4463427
Evolution of secretin family GPCR members in the metazoa [2]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundComparative approaches using protostome and deuterostome data have greatly contributed to understanding gene function and organismal complexity.
- Closing excerpt
- The putative ancestral receptors are proposed to be more like the deuterostome CAL/CGRP and CRF receptors and this may be associated with their fundamental role in calcium regulation and the stress response, both of which are essential for survival.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (308 words)
BackgroundComparative approaches using protostome and deuterostome data have greatly contributed to understanding gene function and organismal complexity. The family 2 G-protein coupled receptors (GPCRs) are one of the largest and best studied hormone and neuropeptide receptor families. They are suggested to have arisen from a single ancestral gene via duplication events. Despite the recent identification of receptor members in protostome and early deuterostome genomes, relatively little is known about their function or origin during metazoan divergence. In this study a comprehensive description of family 2 GPCR evolution is given based on in silico and expression analyses of the invertebrate receptor genes.ResultsFamily 2 GPCR members were identified in the invertebrate genomes of the nematodes C. elegans and C. briggsae, the arthropods D. melanogaster and A. gambiae (mosquito) and in the tunicate C. intestinalis. This suggests that they are of ancient origin and have evolved through gene/genome duplication events. Sequence comparisons and phylogenetic analyses have demonstrated that the immediate gene environment, with regard to gene content, is conserved between the protostome and deuterostome receptor genomic regions. Also that the protostome genes are more like the deuterostome Corticotrophin Releasing Factor (CRF) and Calcitonin/Calcitonin Gene-Related Peptide (CAL/CGRP) receptors members than the other family 2 GPCR members. The evolution of family 2 GPCRs in deuterostomes is characterised by acquisition of new family members, with SCT (Secretin) receptors only present in tetrapods. Gene structure is characterised by an increase in intron number with organismal complexity with the exception of the vertebrate CAL/CGRP receptors.ConclusionThe family 2 GPCR members provide a good example of gene duplication events occurring in tandem with increasing organismal complexity during metazoan evolution. The putative ancestral receptors are proposed to be more like the deuterostome CAL/CGRP and CRF receptors and this may be associated with their fundamental role in calcium regulation and the stress response, both of which are essential for survival.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 17166275 · DOI · PMC1764030
Multiplexed analysis of the secretin-like GPCR-RAMP interactome [3]
Abstract reading summary — source excerpts
- Opening excerpt
- Receptor activity-modifying proteins (RAMPs) have been shown to modulate the functions of several G protein-coupled receptors (GPCRs), but potential direct interactions among the three known RAMPs and hundreds of GPCRs have never been investigated.
- Closing excerpt
- The SBA strategy will be useful to search for additional GPCR-RAMP complexes and other interacting membrane protein pairs in cell lines and tissues.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (148 words)
Receptor activity-modifying proteins (RAMPs) have been shown to modulate the functions of several G protein-coupled receptors (GPCRs), but potential direct interactions among the three known RAMPs and hundreds of GPCRs have never been investigated. Focusing mainly on the secretin-like family of GPCRs, we engineered epitope-tagged GPCRs and RAMPs, and developed a multiplexed suspension bead array (SBA) immunoassay to detect GPCR-RAMP complexes from detergent-solubilized lysates. Using 64 antibodies raised against the native proteins and 4 antibodies targeting the epitope tags, we mapped the interactions among 23 GPCRs and 3 RAMPs. We validated nearly all previously reported secretin-like GPCR-RAMP interactions, and also found previously unidentified RAMP interactions with additional secretin-like GPCRs, chemokine receptors, and orphan receptors. The results provide a complete interactome of secretin-like GPCRs with RAMPs. The SBA strategy will be useful to search for additional GPCR-RAMP complexes and other interacting membrane protein pairs in cell lines and tissues.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 31555726 · DOI · PMC6750928
Secretin targets interstitial cells of Cajal to regulate intestinal contractions [4]
Abstract reading summary — source excerpts
- Opening excerpt
- Secretin is a gastrointestinal (GI) hormone that slows intestinal motility, an effect thought to be mediated through vagal afferent pathways.
- Closing excerpt
- In the case of secretin, integrated responses may serve to slow intestinal transit to enhance digestion and absorption of nutrients.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (163 words)
Secretin is a gastrointestinal (GI) hormone that slows intestinal motility, an effect thought to be mediated through vagal afferent pathways. In this study we show evidence for a novel function of secretin involving a non-neural mechanism mediated by interstitial cells of Cajal (ICC). Transcripts of secretin receptors (Sctr) are expressed abundantly by ICC in the deep muscular plexus (ICC-DMP). Secretin inhibits small intestinal contractions in the presence of the neurotoxin, tetrodotoxin (TTX) and suppresses excitatory enteric neurotransmission. The inhibitory effects of secretin occur through inhibition of Ca2+ transients in ICC-DMP, likely via Gαs-coupled cAMP production and PKA activation that leads to inhibition of IP3 receptors. Our results provide a novel concept for the role of ICC-DMP in small intestinal motility. ICC-DMP serve as integration hubs in which signaling from the enteric nervous system and hormones converge and integrate regulatory responses controlling intestinal motility. In the case of secretin, integrated responses may serve to slow intestinal transit to enhance digestion and absorption of nutrients.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 41198902 · DOI · PMC12678811
Key reviews and meta-analyses
The most cited review-type papers among PubMed’s best-match results for this heading, listed with bibliographic details only. Follow the links for the full text and access terms.
- Research article The trophic action of gastrointestinal hormones [5]
- Research article Gastric inhibitory polypeptide: the neglected incretin revisited [6]
- Research article Secretins: dynamic channels for protein transport across membranes [7]
- Research article Serum gastrin in Zollinger-Ellison syndrome: II. Prospective study of gastrin provocative testing in 293 patients from the National Institutes of Health and comparison with 537 cases from the literature. evaluation of diagnostic criteria, proposal of new criteria, and correlations with clinical and tumoral features [8]
- Research article Secretin, 100 years later [9]
- Research article State-of-the-art pancreatic MRI [10]
References
- Gold VA, Salzer R, Averhoff B, Kühlbrandt W. Structure of a type IV pilus machinery in the open and closed state. . 2015. PMID 25997099 · DOI · PMC4463427
- Cardoso JC, Pinto VC, Vieira FA, Clark MS, Power DM. Evolution of secretin family GPCR members in the metazoa. . 2006. PMID 17166275 · DOI · PMC1764030
- Lorenzen E, Dodig-Crnković T, Kotliar IB, Pin E, Ceraudo E, Vaughan RD, et al.. Multiplexed analysis of the secretin-like GPCR-RAMP interactome. . 2019. PMID 31555726 · DOI · PMC6750928
- Bartlett AM, Blair PJ, Sanders KM, Baker SA. Secretin targets interstitial cells of Cajal to regulate intestinal contractions. . 2025. PMID 41198902 · DOI · PMC12678811
- Johnson LR. The trophic action of gastrointestinal hormones. Gastroenterology. 1976. PMID 765181 · DOI
- Meier JJ, Nauck MA, Schmidt WE, Gallwitz B. Gastric inhibitory polypeptide: the neglected incretin revisited. Regul Pept. 2002. PMID 12137960 · DOI
- Korotkov KV, Gonen T, Hol WG. Secretins: dynamic channels for protein transport across membranes. Trends Biochem Sci. 2011. PMID 21565514 · DOI · PMC3155655
- Berna MJ, Hoffmann KM, Long SH, Serrano J, Gibril F, Jensen RT. Serum gastrin in Zollinger-Ellison syndrome: II. Prospective study of gastrin provocative testing in 293 patients from the National Institutes of Health and comparison with 537 cases from the literature. evaluation of diagnostic criteria, proposal of new criteria, and correlations with clinical and tumoral features. Medicine (Baltimore). 2006. PMID 17108779 · DOI · PMC9817094
- Chey WY, Chang TM. Secretin, 100 years later. J Gastroenterol. 2003. PMID 14673718 · DOI
- Sandrasegaran K, Lin C, Akisik FM, Tann M. State-of-the-art pancreatic MRI. AJR Am J Roentgenol. 2010. PMID 20566796 · DOI
About this article
- Sources
- NLM Medical Subject Headings (definition, synonyms); NCBI PubMed (counts, identifiers); Europe PMC (open-access abstracts and citation counts).
- Verification
- Every reference was resolved against PubMed on 2026-10-31; title, year and DOI matched.
- Review state
- automated source verified; no human expert review has been recorded yet.
- Version
- 1, last updated 2026-10-31.
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Evidence strength
EvidenceHelix's computed view of the study designs behind this topic: how common meta-analyses, randomized trials and reviews are, how recent the literature is, and a plain-language reading. It describes the design mix of the literature. It is not a quality appraisal of any study, and it is not medical advice.