Secretagogue
A substance that stimulates the secretion of an endogenous compound — most commonly applied to GH-releasing peptides.
For laboratory and research use only — not for human consumption.
A secretagogue is any pharmacological agent whose primary action is to trigger the release of an endogenous secreted compound rather than to substitute for it. In peptide research the term is used almost exclusively for compounds that stimulate growth-hormone release from anterior-pituitary somatotrophs — the so-called GH secretagogues. These include endogenous-pathway agonists (GHRH analogues such as sermorelin and tesamorelin that act at the GHRH receptor) and ghrelin-pathway agonists (GHRPs such as ipamorelin, hexarelin, GHRP-2/6, plus the small-molecule MK-677). The mechanistic rationale for secretagogue research over exogenous recombinant growth hormone (somatropin) is that secretagogues preserve the pulsatile pattern of physiological GH release and respect the somatostatin/IGF-1 negative-feedback loop, theoretically reducing the receptor downregulation and supraphysiological IGF-1 elevations associated with exogenous GH. Beyond the GH axis, the term applies to insulin secretagogues (sulphonylureas, GLP-1 analogues) in metabolic-disease research, but this is a separate literature.