What is Growth-hormone-releasing hormone (GHRH)?

The hypothalamic signal that tells the pituitary to release GH. Structurally it is Hypothalamic releasing peptide (44 aa).

How strong is the evidence for GHRH?

PeptideHormone grades GHRH at the "Established" evidence tier — its mechanism and core effects are settled across the peer-reviewed literature. It is catalogued as an endogenous signal the body produces itself, and the tier is an editorial judgment about the public literature that can change as the science does.

What is the half-life of GHRH?

The reported circulating half-life of GHRH is ~7–50 min.

Growth-hormone-releasing hormoneGHRH

The hypothalamic signal that tells the pituitary to release GH.

EndogenousEstablishedCompare lineage

One rung up the axis — the signal that asks for a signal, and the point at which the pituitary reveals itself as a relay rather than a source.

Identity

Class: Hypothalamic releasing peptide (44 aa)
Source: Hypothalamus (arcuate nucleus)
Receptor: GHRH receptor (GHRHR), a class B GPCR

Key properties

Evidence floorClinicalREF1CLIN1

Molecular weight

~5,039.6 Da

REF

Half-life (native)

~7–50 min

CLIN

Model dosing

Approximate values for the native hormone; engineered analogs are often deliberately larger and far longer-acting. Each figure carries its own provenance tier, and the floor is the weakest of them - the Standard.

Mechanism

GHRH from the hypothalamus stimulates pituitary somatotrophs to synthesize and secrete GH, opposed by somatostatin. GHRH analogs are studied as a way to amplify endogenous, still-pulsatile GH rather than supplying GH exogenously.

Reference notes

GHRH and the ghrelin/GHS-R pathway act on different receptors and are synergistic.
Because GHRH works through the pituitary, the resulting GH retains feedback regulation.
Somatostatin opposition is essential to the pulsatile pattern.

Common questions

What is Growth-hormone-releasing hormone (GHRH)?: The hypothalamic signal that tells the pituitary to release GH. Structurally it is Hypothalamic releasing peptide (44 aa).
How does GHRH work?: GHRH from the hypothalamus stimulates pituitary somatotrophs to synthesize and secrete GH, opposed by somatostatin. GHRH analogs are studied as a way to amplify endogenous, still-pulsatile GH rather than supplying GH exogenously.
How strong is the evidence for GHRH?: PeptideHormone grades GHRH at the "Established" evidence tier — its mechanism and core effects are settled across the peer-reviewed literature. It is catalogued as an endogenous signal the body produces itself, and the tier is an editorial judgment about the public literature that can change as the science does.
What is the half-life of GHRH?: The reported circulating half-life of GHRH is ~7–50 min.

Selected literature

Curated peer-reviewed reviews, sourced from PubMed. Selected for relevance, not exhaustive — open any entry on PubMed for the full record and its primary citations.

1.Growth hormone-releasing hormone · Endocrine reviews, 1986 · PMID 2874984
2.Growth hormone-releasing hormone and cancer · Reviews in endocrine & metabolic disorders, 2025 · PMID 39422787

External references

GHRH in the public knowledge graph — the same entity resolved across the authoritative chemistry and protein databases.