Ipamorelin vs Sermorelin: Growth Hormone Secretagogue Comparison
Quick Summary
Ipamorelin and Sermorelin stimulate growth hormone release through completely different receptor systems. Sermorelin is a GHRH analog that acts on the GHRH receptor at the pituitary, while Ipamorelin is a growth hormone-releasing peptide (GHRP) that acts on the ghrelin/GHS receptor. This mechanistic distinction is why researchers study their synergistic potential when used in combination.
Ipamorelin
Research Overview Ipamorelin (NNC 26-0161) is a synthetic pentapeptide growth hormone secretagogue with the sequence Aib-His-D-2-Nal-D-Phe-Lys-NH₂, developed by Novo Nordisk in the mid-1990s by systematic modification of GHRP-1. It acts as a highly selective agonist of the GHS-R1a receptor (ghrelin...
Sermorelin
Sermorelin (GHRH 1-29) is a synthetic 29-amino acid peptide with a molecular weight of 3,357.88 Da. It corresponds to the N-terminal segment of the endogenous 44-amino acid GHRH molecule and is considered the shortest fully functional fragment retaining full biological...
Research Comparison: Ipamorelin vs Sermorelin
| Dimension | Ipamorelin | Sermorelin |
|---|---|---|
| Drug Class | Growth Hormone Releasing Peptide (GHRP) | Growth Hormone Releasing Hormone (GHRH) analog |
| Receptor Target | GHS-R1a (ghrelin/growth hormone secretagogue receptor) | GHRH receptor |
| Structure | Pentapeptide (5 amino acids) | GHRH(1-29)NH₂ (29 amino acids) |
| GH Release Pattern | Acute GH pulse (dose-dependent, specific) | Amplifies natural GH pulsatility |
| Selectivity | Most selective GHRP — no cortisol/prolactin increase | Selective for GH axis; no effect on other pituitary hormones |
| Cortisol Effect | No increase (unique among GHRPs) | No significant change |
| Appetite/Ghrelin | Minimal appetite stimulation (unlike GHRP-6) | No appetite stimulation |
| Synergy | Synergistic with GHRH analogs (different receptor) | Synergistic with GHRPs (different receptor) |
| Clinical Status | Phase II trials (Novo Nordisk); investigational | Previously FDA-approved (Geref); currently investigational |
| Research Focus | GI motility, bone density, body composition | GH deficiency, anti-aging, diagnostic testing |
Chemical Properties Comparison
| Property | Ipamorelin | Sermorelin |
|---|---|---|
| Molecular Formula | C₃₈H₄₉N₉O₅ | C₁₄₉H₂₄₆N₄₄O₄₂S |
| Molecular Weight | 711.85 Da | 3,357.88 Da |
| CAS Number | 170851-70-4 | 86168-78-7 |
| Amino Acid Sequence | — | YADAIFTNSYRKVLGQLSARKLLQDIMSR-NH₂ (29 aa) |
| PubMed Citations | 21 referenced | 20 referenced |
Explore Full Research Profiles
Ipamorelin
Research Overview Ipamorelin (NNC 26-0161) is a synthetic pentapeptide growth hormone secretagogue with the sequence Aib-His-D-2-Nal-D-Phe-Lys-NH₂, developed by Novo Nordisk in the mid-1990s by systematic modification of GHRP-1. It acts as a highly selective agonist of the GHS-R1a receptor (ghrelin...
Sermorelin
Sermorelin (GHRH 1-29) is a synthetic 29-amino acid peptide with a molecular weight of 3,357.88 Da. It corresponds to the N-terminal segment of the endogenous 44-amino acid GHRH molecule and is considered the shortest fully functional fragment retaining full biological...
More Peptide Comparisons
For Research Use Only (RUO). This comparison is for educational and informational purposes only. All products are intended solely for in-vitro research and laboratory experimentation. Products have not been approved by the FDA for human or veterinary use. Pure U.S. Peptides does not condone or encourage the use of these products for anything other than strictly defined research applications.