Somatostatin (SST-14) is an endogenous 14-amino-acid cyclic peptide hormone (MW ~1637.9 g/mol) produced in the hypothalamus, pancreatic delta cells, and gastrointestinal tract. It is a potent inhibitor of growth hormone, insulin, glucagon, gastrin, and numerous other hormones and neurotransmitters. While it served as the basis for the development of clinically successful analogs (octreotide, lanreotide, pasireotide), native somatostatin itself has very limited clinical use due to its extremely short half-life (~1-3 minutes) requiring continuous IV infusion.
Category: Endocrine / Somatostatin Analog. Evidence rating: B (meaningful human data).
Clinical status: Limited clinical use (IV infusion only); synthetic analogs preferred for therapeutic applications
Somatostatin binds to all five somatostatin receptor subtypes (SSTR1-5), which are G-protein-coupled receptors that inhibit adenylyl cyclase. Through these receptors, it exerts broad inhibitory effects: suppression of GH release from the anterior pituitary, inhibition of insulin and glucagon from…
Safety considerations: Extremely short half-life (~1-3 minutes) necessitates continuous IV infusion, limiting practical use; Rebound hypersecretion of hormones (GH, insulin, glucagon) upon discontinuation of infusion; Nausea, abdominal cramps, and diarrhea during infusion.
Reviewed by the PeptideAtlas Editorial Team.
| Amino-acid sequence | Ala-Gly-Cys-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Phe-Thr-Ser-Cys (disulfide bridge Cys3-Cys14) |
|---|---|
| Molecular weight | ~1637.9 g/mol |
| CAS number | 38916-34-6 |
| Half-life | ~1-3 minutes (IV) |
| Production method | synthetic |
| Anti-doping status | not-listed |
| US regulatory status | Not widely marketed as a drug product in the US. Synthetic analogs (octreotide, lanreotide) are preferred. Available as a research reagent. |
Related peptides: Octreotide, Lanreotide, Pasireotide.
Native somatostatin has an extremely short half-life of only 1-3 minutes, requiring continuous intravenous infusion. Synthetic analogs like octreotide (half-life 1.5-2 hours) and lanreotide were developed specifically to overcome this limitation, providing practical subcutaneous and depot injection options.
Both are products of the same preprosomatostatin gene. SST-14 is a 14-amino-acid peptide predominant in the hypothalamus and pancreatic delta cells. SST-28 is a 28-amino-acid form that includes the SST-14 sequence at its C-terminus and is more prevalent in the GI tract. SST-28 has preferential affinity for SSTR5.
Somatostatin was isolated from ovine hypothalamic extracts by Brazeau et al. in 1973 as a 14-amino-acid peptide that inhibited growth hormone release. This work was part of Roger Guillemin's research program on hypothalamic hormones, contributing to his 1977 Nobel Prize in Physiology or Medicine.
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