Ipamorelin, the First Selective Growth Hormone Secretagogue
Raun K, Hansen BS, Johansen NL, Thøgersen H, Madsen K, Ankersen M, Andersen PH
European Journal of Endocrinology · Vol. 139(5) · pp. 552–561 · 1998
Characterization of Ipamorelin as the first highly selective GH secretagogue that stimulates GH release without significantly affecting cortisol, prolactin, or ACTH. Establishes Ipamorelin's superior selectivity profile compared to earlier GHRPs and its potential for clinical GH optimization.
Key Findings
Ipamorelin produces potent, dose-dependent GH release via ghrelin receptor activation
Highly selective — does not significantly stimulate cortisol, prolactin, or ACTH release
GH pulse amplitude comparable to GHRP-6 but with dramatically cleaner hormonal profile
Effective via subcutaneous injection with rapid onset (15–30 min peak GH)
No tachyphylaxis observed with repeated dosing in animal studies
Methodology
In vitro pituitary cell GH release assays combined with in vivo rat and pig GH secretion studies. Hormonal selectivity profiling vs. GHRP-2, GHRP-6, and hexarelin.
Limitations
Animal pharmacology data; human clinical trials limited. Optimal dosing protocols for human GH optimization established empirically.
Protocols Using This Research
Tags
Educational use only. Research summaries are provided for informational purposes. Always consult the original publication and a qualified healthcare provider before making clinical decisions.
Related Research
Prolonged Stimulation of Growth Hormone and Insulin-Like Growth Factor 1 Secreti…
2006 · Strong Evidence
Ipamorelin, the First Selective Growth Hormone Secretagogue
1998 · Strong Evidence
Prolonged Stimulation of Growth Hormone (GH) and Insulin-Like Growth Factor I Se…
2006 · Strong Evidence
Regulation of Muscle Mass by Follistatin and Activins
2001 · Moderate Evidence
Build a protocol around this research
Our AI Advisor incorporates the latest research to build a personalized peptide protocol for your goals.
Start Assessment