Ipamorelin
Ipamorelin is a selective pentapeptide GHS-R1a agonist for in vitro investigation of the ghrelin/GH-secretagogue axis. Characterized in preclinical literature as a clean GH-releasing tool with minimal cortisol, prolactin, or ACTH cross-activation.
Independently Tested. Verifiably Pure.
Every batch of Ipamorelin is sent to an accredited independent laboratory before it ships. Here is exactly what we screen for - and the certificate that proves it.
What We Test Every Batch For
How Ipamorelin Works
Selective GHS-R1a signaling characterized across in vitro and animal-model GH-axis research
Selective GHS-R1a Agonism
Ipamorelin is a synthetic pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH₂) that binds the growth hormone secretagogue receptor 1a (GHS-R1a), the same receptor activated by endogenous ghrelin. The Aib (aminoisobutyric acid) residue and D-amino-acid backbone confer protease resistance and receptor selectivity in binding assays.
- Pentapeptide ghrelin-mimetic backbone
- High-affinity binding at GHS-R1a in receptor assays
- Aib residue stabilizes the active conformation
GH Release Without Cortisol/Prolactin Elevation
Raun et al. (1998) and subsequent comparative studies characterized ipamorelin as the first GHRP capable of stimulating pituitary GH release in animal models without significantly elevating cortisol, ACTH, or prolactin — distinguishing it from earlier GHRPs such as GHRP-6 and hexarelin.
- Robust GH release in rat & swine preclinical models
- No measurable cortisol or ACTH elevation at GH-active doses
- No significant prolactin spike vs. GHRP-6 controls
Pulsatile GH Pathways in Preclinical Models
GHS-R1a agonism preserves the hypothalamic-pituitary feedback loop, allowing GH release to remain pulsatile rather than tonic. Ipamorelin is widely used in research as a probe for studying somatostatin opposition, ghrelin-axis pharmacology, and synergy with GHRH analogs.
- Preserves pulsatile GH secretion architecture
- Synergistic GH response when paired with GHRH analogs
- Standard reference compound in GHS-R comparative work
What Research Has Shown
Key findings from in vitro receptor assays and animal-model GH-axis publications
Research Applications
Primary preclinical areas where ipamorelin is used as a research tool
GHS-R Receptor Biology Research
Used as a high-affinity ligand in binding, displacement, and signaling assays at the GHS-R1a (ghrelin) receptor, including studies of receptor conformational dynamics and beta-arrestin recruitment in cell-based systems.
Raun et al. 1998 ↗GH-Axis Selectivity Studies
Reference compound in studies dissecting selective GH release from broader pituitary hormone activation. Comparative work shows minimal cortisol, ACTH, and prolactin response — a defining selectivity profile vs. older GHRPs.
Aimaretti et al. 2002 ↗Comparative GHRP Pharmacology
Used as a benchmark in head-to-head GHRP comparisons (GHRP-6, GHRP-2, hexarelin), informing structure-activity work on the ghrelin/GHS-R1a system and downstream Gq/11 signaling.
Smith 2005 ↗Pulsatile-Secretion Preclinical Research
Animal-model probe for studying GH pulsatility, somatostatin/GHRH integration, and synergy with GHRH analogs in research blends — widely paired with CJC-1295 in preclinical GH-axis investigations.
Sinha et al. 2005 ↗Compound Information
Analytical profile and reference data for in vitro research
Frequently Asked Questions
Common questions about ipamorelin research parameters
Sources & References
Peer-reviewed publications and preclinical literature