Somatostatin
Somatostatin (growth hormone inhibiting hormone)
The natural hormone that switches off growth hormone release; its analogues like octreotide are approved drugs.
Overview
Somatostatin is the body's natural brake on growth hormone, opposing GHRH and ghrelin. It also suppresses several digestive and pancreatic hormones. Because native somatostatin is very short-lived, longer-acting analogues such as octreotide were developed and are FDA-approved for acromegaly and hormone-secreting tumors. Somatostatin itself frames how the GH axis is regulated.
Mechanism of action
Activates somatostatin receptors to inhibit growth hormone, insulin, glucagon, and various gastrointestinal hormones.
Key studies & citations
- In vitro1973
Hypothalamic polypeptide that inhibits the secretion of immunoreactive pituitary growth hormone
Discovery and sequencing of somatostatin from ovine hypothalamus; the 14-amino-acid peptide inhibited GH secretion in vitro and in rats.
Science - Review1983
Somatostatin
Classic two-part review of somatostatin physiology as the inhibitory regulator of GH and gut and pancreatic hormones.
New England Journal of Medicine - Review1999
Somatostatin and its receptor family
Reviews somatostatin as an endogenous inhibitory regulator acting through five receptor subtypes, the basis for analogue drug design.
Frontiers in Neuroendocrinology
Frequently asked questions
How does somatostatin relate to growth hormone peptides?
It is the opposite signal: GHRH and ghrelin release growth hormone, while somatostatin shuts it off. Together they set the pulsatile rhythm of GH.