Ghrelin

Definition

• [educational] The stomach ‘hunger hormone’; a natural agonist of the growth-hormone-secretagogue receptor (GHSR-1A), released with fasting.

Why it matters

• [educational] Ghrelin amplifies GHRH-driven GH release and inhibits Somatostatin; the GHRPs (Ipamorelin, GHRP-6, GHRP-2, Hexarelin) and MK-677 mimic it — hence their shared hunger side effect.