PeptideHormone

Growth-hormone-releasing hormoneGHRH

The hypothalamic signal that tells the pituitary to release GH.

EndogenousEstablished

Identity

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

Key properties

Molecular weight
~5,039.6 Da
Half-life (native)
~7–50 min
Model dosing

Approximate values for the native hormone. Engineered analogs are often deliberately larger and far longer-acting.

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.

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