Ipamorelin, a third-generation GHS-R1a agonist CAS 170851-70-4 , stimulates pulsatile growth hormone release without elevating cortisol or prolactin, unlike earlier GHRPs. This selectivity supports precise research into GH axis effects, IGF-1 pathways, body composition, recovery, and sleep. Studies…
# Ipamorelin: Selective GH Secretagogue for Clean Pulsatile Release
Ipamorelin stands out as a third-generation GHS-R1a agonist that prompts pulsatile growth hormone release. Unlike prior compounds, it avoids co-secretion of cortisol and prolactin. This feature positions it as a precise tool for GH axis investigations.
Ipamorelin carries the CAS number 170851-70-4, with molecular formula C₃₈H₄₉N₉O₅ and molecular weight 711.85 Da. As a synthetic pentapeptide in the growth hormone secretagogue class, its sequence is Aib-His-D-2-Nal-D-Phe-Lys-NH₂. Two non-natural amino acids in this sequence contribute to its specific pharmacological properties.
It functions as a third-generation growth hormone-releasing peptide. By binding to GHS-R1a, the ghrelin receptor on pituitary somatotroph cells, it initiates natural pulsatile growth hormone secretion.
First-generation GHRP-6 effectively boosts GH but raises cortisol, prolactin, and appetite through off-target effects. These side effects complicate studies focused solely on GH impacts.
Second-generation GHRP-2 offers greater potency than GHRP-6, yet it still causes notable cortisol increases. This limits its use in research on metabolism, stress, or immunity.
Third-generation Ipamorelin prioritizes receptor selectivity. Preclinical comparisons show it matches or exceeds GH pulse strength of earlier GHRPs, with almost no cortisol or prolactin elevation. Researchers favor it for isolated GH data.
Ipamorelin mainly induces clean, pulsatile GH from the anterior pituitary. This pattern echoes natural physiological pulses, unlike steady elevations, which matter for GH receptor studies where pulse timing alters outcomes.
The GH it releases promotes hepatic IGF-1 production. Insulin-like growth factor 1 mediates GH's anabolic actions, including protein synthesis, muscle cell growth, connective tissue repair, and bone density. Models using Ipamorelin examine these IGF-1 pathways in muscle, tendon, and bone.
The GH-IGF-1 axis influences body composition. Animal research with Ipamorelin explores lean mass maintenance, visceral fat reduction, and body ratio shifts, independent of appetite or calorie changes.
Natural GH secretion peaks during slow-wave sleep. Studies assess Ipamorelin's pulsatile action in sleep research, checking if it syncs with or boosts the sleep-related GH surge.
IGF-1 signaling activates muscle satellite cells, remodels connective tissue, and aids wound healing. Preclinical models employ Ipamorelin to investigate these repair mechanisms in muscle and tendon post-exercise damage.
For precise dosing in such studies, check the Dosage & Cycle Planner /tools/peptide-dosage-planner .
Ipamorelin and CJC-1295 target distinct receptors without overlap. Ipamorelin mimics ghrelin at GHS-R1a for GH pulses, while CJC-1295, a GHRH analog, binds GHRH receptors to heighten pulse size and length.
Together, they yield far higher GH levels than alone. This stack appears often in research protocols. See the Peptide Glossary /tools/peptide-glossary for terms like GHS-R1a.
Store lyophilized form at −20°C for up to 24 months. Keep reconstituted solution at 2, 8°C for up to 4 weeks, shielded from light. Use the Reconstitution Calculator /tools/peptide-reconstitution-calculator for accurate preparations.
Browse research compounds in our catalog /catalog .
Ipamorelin CAS 170851-70-4, MW 711.85 Da, sequence Aib-His-D-2-Nal-D-Phe-Lys-NH₂ selectively activates GHS-R1a for pulsatile GH release. It outperforms GHRP-6 and GHRP-2 in cleanliness, supporting studies on IGF-1, fat loss, protein synthesis, recovery, and sleep. For research use only; not for human consumption.
Ipamorelin incorporates alpha-aminoisobutyric acid at position 1 and D-2-naphthylalanine at position 3 for better GHS-R1a specificity. This yields strong GH pulses with minimal side hormones.
References
1. Raun K, Hansen BS, Johansen NL, et al. “Ipamorelin, the first selective growth hormone secretagogue.” European Journal of Endocrinology 1998 . https://pubmed.ncbi.nlm.nih.gov/9678806/
2. Bowers CY. “Growth hormone-releasing peptide GHRP .” Cellular and Molecular Life Sciences 1998 . https://pubmed.ncbi.nlm.nih.gov/9885515/
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Looking for high-purity research peptides? Browse our catalog for HPLC-verified compounds.
| Compound | Purity | Size | Price |
|---|---|---|---|
| Ipamorelin 10mg /product/ipamorelin-10mg | ≥98% | 10mg | $49.00 |
| CJC-1295 No DAC + Ipamorelin 10mg 5+5 /product/cjc-1295-no-dac-ipamorelin-10mg | ≥98% | 10mg | $49.00 |
| CJC-1295 DAC 5mg /product/cjc-1295-dac-5mg | ≥98% | 5mg | $49.00 |
| CJC-1295 No DAC 10mg /product/cjc-1295-no-dac-10mg | ≥98% | 10mg | $49.00 |
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Peptides referenced: Ipamorelin, CJC-1295, GHRP-6, GHRP-2, Growth Hormone, IGF-1, Ghrelin, CJC-1295 with DAC.
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