IPAMORELIN

Ipamorelin (5mg)

Ipamorelin was first introduced in the late 1990s as a highly selective growth hormone–releasing peptide. It belongs to a newer class of compounds designed to stimulate the pituitary gland through ghrelin-receptor activation while minimizing unwanted hormonal responses. Unlike earlier molecules such as GHRP-6, Ipamorelin increases growth hormone levels without elevating cortisol or prolactin in research settings.

In laboratory studies, Ipamorelin has been examined for its effects on muscle protein synthesis, bone density, and metabolic regulation. This precision and favorable safety profile have made this peptide a major focus in research on growth hormone modulation and endocrine system regulation.

What Is Ipamorelin?

What is Ipamorelin? It is a synthetic pentapeptide first developed by researchers exploring safer and more selective growth-hormone secretagogues. Classified as a selective growth hormone–releasing peptide, Ipamorelin works by binding to ghrelin receptors on the pituitary gland. [1]

This interaction stimulates GH release and triggers the secretion of growth hormone without significantly affecting cortisol or prolactin. Compared with older GHRPs such as GHRP-2 and GHRP-6, Ipamorelin offers higher receptor selectivity and cleaner hormonal activity. This makes it a preferred peptide for controlled growth hormone and peptide therapy research applications.

Molecular Structure and Mechanism of Action

The Ipamorelin peptide has a well-defined molecular structure that supports its precision and stability. It was designed to act selectively on ghrelin receptors involved in growth hormone release and to complement the action of growth hormone-releasing hormone (GHRH), while avoiding cross-reactivity with other pituitary hormones.

• Peptide Sequence: Aib-His-D-2-Nal-D-Phe-Lys-NH₂

• Molecular Formula: C₃₈H₄₉N₉O₅

• Molecular Weight: 711.9 g/mol

• CAS Number: 170851-70-4

• PubChem CID: 9831659

• Synonyms: Ipamorelin acetate, NNC 26-0161

Ipamorelin activates the ghrelin receptor (GHSR-1a), stimulating a controlled pulse of natural growth hormone from the pituitary gland. Unlike earlier peptides, it does not increase cortisol or prolactin secretion.

In research settings, this selective mechanism allows scientists to examine growth hormone physiology without interference from secondary hormonal fluctuations, reinforcing its value as a reliable tool in endocrine and metabolic studies.

Ipamorelin Research Applications

Ipamorelin peptides are widely studied for their diverse research potential, particularly for their ability to release growth hormone. Under controlled conditions, scientists have examined their influence on bone density, muscle recovery, metabolism, and gastrointestinal motility.

Research also explores their role in insulin sensitivity and endocrine signaling. These studies help clarify how selective growth-hormone secretagogues affect tissue repair, energy balance, and hormonal regulation.

Role in Bone Health and Density Research

Ipamorelin has gained research interest for its influence on bone health and density. In laboratory studies, it stimulates growth hormone release, which affects bone metabolism and remodeling. These experiments also help researchers observe how skeletal changes relate to the natural decline in growth hormone activity. Researchers use osteoblast and osteoclast cultures, as well as animal models, to measure changes in bone mineral density.

Results show enhanced collagen synthesis and improved bone microarchitecture after Ipamorelin administration. [2] Compared with other growth hormone secretagogues, Ipamorelin demonstrates greater receptor selectivity and stable anabolic signaling. These findings highlight its value in exploring skeletal maintenance and bone regeneration mechanisms.

Studies on Muscle Growth, Recovery, and Growth Hormone Levels

Ipamorelin is being studied for its effects on muscle growth, recovery, and growth hormone levels. It has been observed to bind selectively to ghrelin receptors, triggering growth hormone release from the pituitary gland. Researchers examine its impact on muscle regeneration, increased lean muscle mass, tissue repair, and protein synthesis using in vivo and in vitro models.

Findings show measurable increases in GH and IGF-1 markers. [3] Unlike other secretagogues, Ipamorelin does not raise cortisol or prolactin. These characteristics make it valuable for understanding muscle recovery and anabolic regulation in experimental research, particularly in relation to the aging process, including ongoing studies examining Ipamorelin therapy and its mechanisms.

Research on Metabolism and Insulin Sensitivity

Ipamorelin is also being studied for its influence on metabolism, insulin sensitivity, body composition, and fat loss mechanisms. In laboratory research, it activates ghrelin receptors linked to glucose regulation and insulin signaling. Scientists use animal and cell-based models to assess glucose uptake, lipid and fat metabolism, and energy balance. [4] Findings show Ipamorelin may alter fasting glucose and insulin responses under controlled conditions.

Studies also measure changes in metabolic enzyme activity and mitochondrial performance. Compared with other growth hormone secretagogues, Ipamorelin demonstrates selective action without increasing cortisol, supporting focused research on metabolic function and insulin regulation.

Investigations Into Gastrointestinal Motility and Post-Operative Ileus

Other areas where Ipamorelin is being explored include its potential influence on gastrointestinal motility and post-operative ileus. Researchers examine how it activates ghrelin receptors that regulate intestinal movement. Experimental models, including animal and ex-vivo systems, measure its impact on smooth muscle contractions and gut coordination.

Studies monitor changes in gastric emptying and bowel transit after Ipamorelin administration. [5] Results suggest improved motility compared with other ghrelin-agonists. These findings help researchers better understand how selective peptides influence digestive function and recovery mechanisms in gastrointestinal research. [6]

Ipamorelin as a Ghrelin Receptor Probe in Endocrine Studies

Ipamorelin serves as a precise ghrelin receptor probe in endocrine research. Its high selectivity for the GHSR-1a receptor allows scientists to study hormone release with minimal interference from other pituitary pathways. Researchers use receptor-binding assays and molecular imaging to trace endocrine responses. [7]

These methods help map how ghrelin receptor stimulation links to growth hormone secretion and metabolic activity. Techniques such as radioligand binding and gene expression analysis reveal Ipamorelin’s reliability in isolating endocrine effects and advancing research on hormonal communication.

In some endocrine experiments, study frameworks resembling a treatment plan are used to maintain consistent dosing intervals and accurately measure hormonal responses over time.

Neuroprotective and Anti-Inflammatory Research Potential

Ipamorelin has drawn interest for its potential neuroprotective and anti-inflammatory effects under experimental conditions. Researchers study its ghrelin receptor activity to understand how it may protect neurons from oxidative stress and inflammation. [8] In vitro and in vivo models assess its influence on cytokine release, glial activation, and neuronal survival pathways.

Findings show changes in molecular markers such as NF-κB, IL-6, and TNF-α. Because of its receptor selectivity, Ipamorelin allows scientists to study neural signaling and cellular protection without disrupting broader endocrine systems. Some studies also examine secondary cellular responses related to collagen support, improved skin elasticity, and anti-aging effects under controlled laboratory conditions.

Comparative Studies Among Growth Hormone Releasing Peptides

Comparative studies show how Ipamorelin differs from other growth hormone–releasing peptides such as CJC-1295, GHRP-2, and GHRP-6. These studies have shown that Ipamorelin's selective mechanism triggers growth hormone release without affecting cortisol or prolactin. They also compare receptor binding, hormonal specificity, and half-life across peptides, with some surprising results. [9]

Ipamorelin demonstrates a cleaner pharmacological profile and more stable human growth hormone (hGH) pulse regulation, both considered key benefits of Ipamorelin in comparative research. Ongoing research explores combined use with CJC-1295 to examine synergistic growth hormone modulation. These comparisons continue to guide investigations into peptide selectivity, cellular regeneration, and advanced endocrine research applications.

Laboratory Testing and Product Verification

Laboratory testing ensures the accuracy, purity, and consistency of Ipamorelin before research use. Analytical methods such as high-performance liquid chromatography (HPLC) and mass spectrometry (MS) confirm its molecular weight and purity level. Peptide mapping and amino acid sequencing verify that the structure matches the reference standard.

Each Ipamorelin product comes with a verified Certificate of Analysis (COA) that outlines essential quality data, including lot number, purity percentage, and analytical results. We conduct third-party or in-house validation for every batch to ensure full traceability and compliance with laboratory-grade standards.

Researchers who buy Ipamorelin from Peptides Online receive a verified peptide that meets rigorous specifications for reliability, stability, and structural accuracy, supporting consistent outcomes across scientific and experimental applications.

Storage and Handling Guidelines

Proper storage and handling are vital to maintain Ipamorelin’s stability and integrity. Lyophilized Ipamorelin should be kept in a sealed vial, stored at –20°C, and protected from light and moisture. Before reconstitution, avoid exposing it to temperature fluctuations. Researchers typically reconstitute the peptide with sterile bacteriostatic water and mix it gently to prevent denaturation.

Once reconstituted, it should be refrigerated between 2°C and 8°C and used within a short period. For long-term storage, aliquoting the solution minimizes freeze–thaw cycles. Labeling and aseptic technique help preserve purity, sterility, and consistency during all experimental applications.

Disclaimer:

Ipamorelin is intended strictly for laboratory research purposes. It is not approved for human, veterinary, or diagnostic use. This peptide must be handled only by trained professionals in controlled research environments following proper safety and compliance standards. The information provided here is for scientific and educational reference only. It should not be used as medical, therapeutic, or legal advice. Researchers are responsible for ensuring that all testing, storage, and handling practices meet institutional, ethical, and regulatory requirements before using this product in any experiment.

References and Supporting Literature

1. Raun, K., Hansen, B. S., Johansen, N. L., Thøgersen, H., Madsen, K., Ankersen, M., & Andersen, P. H. (1998). Ipamorelin, the first selective growth hormone secretagogue. European Journal of Endocrinology, 139(5), 552–561. PubMed 

2. Svensson, J., Lall, S., Dickson, S. L., Bengtsson, B. A., Rømer, J., Ahnfelt-Rønne, I., Ohlsson, C., & Jansson, J. O. (2000). The GH secretagogues ipamorelin and GH-releasing peptide-6 increase bone mineral content in adult female rats. Journal of Endocrinology, 165(3), 569–577. PubMed 

3. Raun, K., Hansen, B., Johansen, N. L., Thøgersen, H., Madsen, K., Ankersen, M., & Andersen, P. (1998). Ipamorelin, the first selective growth hormone secretagogue. European Journal of Endocrinology, 139(5), 552–561. ResearchGate 

4. Adeghate, E., & Ponery, A. (2004). Mechanism of ipamorelin-evoked insulin release from the pancreas of normal and diabetic rats. Neuro Endocrinology Letters, 25(6), 403–406. PubMed 

5. Greenwood-Van Meerveld, B., Tyler, K., Mohammadi, E., & Pietra, C. (2012). Efficacy of ipamorelin, a ghrelin mimetic, on gastric dysmotility in a rodent model of postoperative ileus. Journal of Experimental Pharmacology, 4, 149–155. PMC 

6. Polvino, W. J., Nelson, R., & Mann, W. R. (2011). Method of stimulating the motility of the gastrointestinal system using ipamorelin. U.S. Patent No. US 8039456 B2. Google Patents 

7. Abizaid, A., & Hougland, J. L. (2019). Ghrelin signaling: GOAT and GHS-R1a take a LEAP in complexity. Endocrinology, 161(7), bqaa061. PMC 

8. Müller, T. D., Nogueiras, R., Andermann, M. L., Andrews, Z. B., Anker, S. D., Argente, J., … & Tschöp, M. H. (2015). Ghrelin. Molecular Metabolism, 4(6), 437–460. ScienceDirect 

9. Sigalos, J. T., & Pastuszak, A. W. (2018). The safety and efficacy of growth hormone secretagogues. Sexual Medicine Reviews, 6(1), 45–53. PMC