GH secretagogue
Also known as: growth hormone secretagogue, GHS
Definition
GH secretagogues are a broad class of compounds that enhance the secretion of growth hormone from the anterior pituitary gland. This class includes peptide-based secretagogues (such as GHRH analogues and ghrelin receptor agonists) and non-peptide small-molecule secretagogues that may act through alternative pathways. GH secretagogues function by either directly stimulating GH-releasing hormone receptors, activating ghrelin receptors, or inhibiting somatostatin (which normally suppresses GH release). Research distinguishes between these mechanisms and investigates how different secretagogues compare in terms of potency, duration of action, and specificity for growth hormone versus other hormones.
The physiological control of GH secretion involves complex interactions between stimulatory signals (GHRH and ghrelin) and inhibitory signals (somatostatin and feedback from IGF-1). GH secretagogues are characterized by which pathway they preferentially target and how they integrate into this regulatory network. Some research compounds act specifically on single targets, while others exhibit activity across multiple GH-regulating pathways, providing opportunities to study mechanistic questions about GH control.
Comparative research on GH secretagogues has examined their effects on pulsatile GH secretion, IGF-1 production, metabolic parameters, and body composition. The pharmacodynamic profiles of different secretagogues—including onset time, peak effect, and duration of action—are important for understanding their utility in research and potential clinical applications. Regulatory evaluation of secretagogues has historically focused on characterizing these profiles and identifying any off-target effects or safety signals.