Growth Hormone (GH)
Definition
The pituitary hormone released in pulses that influences growth, body composition and metabolism. Most of its longer-term effects are mediated indirectly, through IGF-1 produced in the liver in response to it.
Terms used in this definition
Other entries this definition refers to.
Where this term comes up
Entries whose definition mentions Growth Hormone (GH).
What this means for research sourcing
Mechanistic terms like this describe how research compounds behave in vitro. See the mechanism overviews for compounds Volta stocks.
Related Terms in Pharmacology
Growth Hormone Secretagogue (GHS)
Any compound that makes the pituitary release its own growth hormone rather than supplying growth hormone itself. Ipamorelin, the GHRPs and MK-677 all fall in the class, and so do the GHRH analogues by a different receptor.
Secretagogue
A compound that causes something else to be secreted. In peptide work the something else is almost always growth hormone, which is why the word usually appears as part of growth hormone secretagogue.
GHRP (Growth Hormone Releasing Peptide)
A family of synthetic peptides that release growth hormone by activating the ghrelin receptor. GHRP-2, GHRP-6, hexarelin and ipamorelin belong to it, and they differ in how much hunger, cortisol and prolactin signalling they bring with them.
GHRH (Growth Hormone Releasing Hormone)
The hypothalamic hormone that instructs the pituitary to synthesise and release growth hormone. Sermorelin, tesamorelin and CJC-1295 are analogues of it, and they act at a different receptor from the GHRPs, which is the basis for studying the two together.
GHS-R1a (Growth Hormone Secretagogue Receptor)
The ghrelin receptor, a G protein-coupled receptor expressed mainly in the pituitary and hypothalamus. Activation by ghrelin or by a GHRP produces a growth hormone pulse along with appetite and reward signalling.
Somatostatin
The hypothalamic hormone that brakes growth hormone release, acting as the counterweight to GHRH. The alternation between the two is what makes natural growth hormone secretion pulsatile rather than continuous.
Pulsatile Release
Secretion in bursts rather than at a steady level. Growth hormone and GnRH are both pulsatile, and the pattern carries information: continuous stimulation of a GnRH receptor suppresses the axis it would otherwise drive.
IGF-1 (Insulin-Like Growth Factor 1)
A liver-produced hormone that mediates much of what growth hormone does to growth, metabolism and body composition. Serum IGF-1 is the usual laboratory proxy for growth hormone exposure because it is stable where GH itself is pulsatile.