GHRP-6 and the oral GHS NN703 were concentrated in gastric tissue (where ghrelin is produced), raising the possibility that GH secretagogues partly work by stimulating endogenous ghrelin release from the stomach.
Stomach accumulationBoth GHRP-6 and oral NN703 concentrated in gastric tissue containing ghrelin cells — suggesting a ghrelin-releasing secondary mechanism
What the researchers found
GHRP-6 and the oral GHS NN703 concentrated in rat gastric tissue containing ghrelin-producing cells, suggesting GH secretagogues may act partly by stimulating endogenous ghrelin release as a secondary mechanism.
Why it matters
If GH secretagogues stimulate the body's own ghrelin release, their effects would be more physiological and sustained than simple receptor mimicry, changing how we understand their mechanism.
How the study worked
Animal study using radiolabeled GHRP-6 and NN703 for tissue distribution analysis in rats, focusing on gastric tissue accumulation relative to ghrelin-producing cell localization.
What this study cannot tell us
Tissue distribution doesn't prove ghrelin release stimulation. The stomach accumulation could reflect metabolism or excretion rather than receptor-mediated targeting. Ghrelin release was not directly measured.
How to read the evidence
Preliminary animal evidence from tissue distribution studies providing an intriguing but unproven mechanistic hypothesis.
When this study was published
Published in 2001. The question of whether GH secretagogues stimulate endogenous ghrelin remains active in the field.
The bigger picture
Understanding the full mechanism of GH secretagogues matters for optimizing therapy. If they work partly through ghrelin release, their effects depend on stomach function — which varies between patients.
Questions still open
- Does stomach GH secretagogue accumulation actually trigger ghrelin release?
- Would gastric bypass surgery reduce GH secretagogue effectiveness?
- Can this mechanism be exploited to develop better ghrelin-releasing agents?
Common questions
Do GH peptides make your stomach release ghrelin?
Does this affect people who've had stomach surgery?
Read the original research
Do growth hormone-releasing peptides act as ghrelin secretagogues?
Endocrine, 14(1), 133-5
Citation
Ahnfelt-Rønne, I; Nowak, J; Olsen, U B. (2001). Do growth hormone-releasing peptides act as ghrelin secretagogues?. Endocrine, 14(1), 133-5.