Ipamorelin

Ipamorelin is an amidated synthetic pentapeptide containing Aib and D-amino acid residues, studied as a GH secretagogue.

Identity

Sequence

H-[Aib]H[D-2Nal][D-Phe]K-NH2

Residues

5

Molecular formula

C₃₈H₄₉N₉O₅

Average molecular weight

711.9 g/mol

Monoisotopic mass (calculated)

711.3857 Da

CAS number

170851-70-4

PubChem CID

9831659

Strengths

5–10 mg

Other names

NNC 26-0161

Identity data from: PubChem CID 9831659

Research overview

Ipamorelin is a synthetic five-residue peptide with an amidated C terminus and the sequence Aib-His-D-2Nal-D-Phe-Lys. The original characterization places it among growth hormone secretagogues and describes its development from a peptide series related to GHRP-1 [1]. Experiments in primary rat pituitary cells, rats and swine examined growth hormone release. Antagonist experiments distinguished its signaling through a GHRP-like receptor from signaling initiated by growth hormone-releasing hormone [1]. The peptide series lacked GHRP-1’s central Ala-Trp dipeptide [1].

A separate study examined skeletal measurements in adult female rats. The investigators compared ipamorelin with GHRP-6 and growth hormone, using X-ray absorptiometry, computed tomography and measurements of isolated bones [2]. They reported greater bone mineral content alongside larger bone dimensions, while volumetric mineral density remained unchanged. Femurs were examined by peripheral quantitative computed tomography. Excised femurs and lumbar vertebrae were also assessed using Archimedes’ principle and ash weight measurements [2].

Another cited paper describes ipamorelin as a ghrelin receptor agonist and examines gastrointestinal transit in a rat model of postoperative ileus [3]. Its measurements included the timing of bowel movement and fecal output after intestinal manipulation. The work used male rats and a dye marker to measure colonic transit time, defined as the interval to the first bowel movement [3].

Laboratory storage and handling

Store the closed container cold, dry and protected from light under the conditions specified for the lot. Let it reach room temperature before opening to limit condensation. Avoid repeated freezing and thawing of laboratory stocks. Record storage history and lot identity alongside experiments, and use standard laboratory protective equipment when handling the material.

Questions about Ipamorelin

References

1. Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol 1998. PMID 9849822
2. The GH secretagogues ipamorelin and GH-releasing peptide-6 increase bone mineral content in adult female rats. J Endocrinol 2000. PMID 10828840
3. Efficacy of ipamorelin, a novel ghrelin mimetic, in a rodent model of postoperative ileus. J Pharmacol Exp Ther 2009. PMID 19289567

Identity data checked on 2026-09-24. Literature summaries describe published research models and are not specifications of any product lot.