Ipamorelin — Research Peptide Overview, Specifications, and Sourcing

At-a-Glance Specifications

CAS Number

170851-70-4

Molecular Weight

711.85 g/mol

Molecular Formula

C₃₈H₄₉N₉O₅

Amino Acid Sequence

Aib-His-D-2-Nal-D-Phe-Lys-NH₂ (pentapeptide)

Purity

≥99% (HPLC verified)

Physical Form

Lyophilized powder

Storage

-20°C lyophilized; 2-8°C reconstituted

Synonyms

Ipamorelin acetate, NNC 26-0161, IPAM

What Is Ipamorelin?

Ipamorelin is a synthetic pentapeptide growth hormone secretagogue (GHS) that selectively stimulates growth hormone (GH) release from the anterior pituitary gland through activation of the growth hormone secretagogue receptor (GHS-R1a), also known as the ghrelin receptor. First described by Raun et al. (1998), ipamorelin was developed by Novo Nordisk as a highly selective GHS that promotes growth hormone release without significantly affecting other pituitary hormones such as ACTH, cortisol, prolactin, or FSH/LH.

Ipamorelin’s selectivity profile distinguishes it from earlier growth hormone secretagogues such as GHRP-6 and GHRP-2, which also stimulate ACTH and cortisol release. This selectivity makes ipamorelin particularly attractive for research applications where GH-specific effects need to be studied in isolation from confounding hormonal changes. The peptide consists of five amino acid residues including two non-natural amino acids (alpha-aminoisobutyric acid and D-2-naphthylalanine), which contribute to its receptor selectivity and metabolic stability.

With a molecular weight of 711.85 g/mol, ipamorelin is a relatively small peptide with favorable pharmacokinetic properties. It acts rapidly with peak GH release occurring approximately 40 minutes after administration in research models, and its effects are dose-dependent, allowing researchers to titrate GH stimulation precisely. The peptide has been the subject of extensive preclinical research and early-phase clinical studies examining its effects on growth hormone pulsatility, body composition, bone metabolism, and recovery processes.

For wholesale research suppliers, ipamorelin is a consistently high-demand compound driven by the robust and growing field of growth hormone research. Its selectivity, well-characterized pharmacology, and extensive literature base make it a preferred tool compound for GH-related investigations across academic, pharmaceutical, and contract research settings.

Mechanism of Action

Ipamorelin stimulates growth hormone release through a specific receptor-mediated mechanism that is distinct from growth hormone-releasing hormone (GHRH) signaling.

GHS-R1a (Ghrelin Receptor) Activation

Ipamorelin binds to and activates the growth hormone secretagogue receptor type 1a (GHS-R1a), a G protein-coupled receptor primarily expressed on somatotroph cells of the anterior pituitary gland. Receptor activation triggers intracellular calcium mobilization through the phospholipase C/IP3 signaling cascade, which directly stimulates GH vesicle exocytosis. Raun et al. (1998) characterized ipamorelin’s selectivity profile, demonstrating potent GH release with minimal effects on ACTH, cortisol, and prolactin (PMID: 9849822).

Selective Growth Hormone Release

Unlike other GHS-R1a agonists that stimulate multiple pituitary hormones, ipamorelin demonstrates remarkable selectivity for GH release. Studies have shown that ipamorelin stimulates GH secretion at doses that do not significantly elevate ACTH, cortisol, prolactin, TSH, or gonadotropin levels. This selectivity has been attributed to the specific binding orientation of ipamorelin within the GHS-R1a binding pocket, which activates GH-specific intracellular signaling cascades while avoiding pathways leading to broader pituitary stimulation.

GH Pulsatility Enhancement

Ipamorelin has been shown to amplify the natural pulsatile pattern of GH release rather than creating an unphysiological sustained elevation. Anderson et al. (2001) demonstrated that ipamorelin enhanced both the amplitude and frequency of GH pulses in a manner that preserved the endogenous GH secretory pattern (PMID: 11713213).

Synergy with GHRH Signaling

Ipamorelin acts through a mechanism complementary to GHRH. While GHRH activates the GHRH receptor (a Gs-coupled GPCR that signals via cAMP), ipamorelin activates GHS-R1a (a Gq-coupled GPCR that signals via IP3/calcium). This mechanistic complementarity means that co-administration of ipamorelin with GHRH analogs (such as CJC-1295) produces synergistic GH release that exceeds the sum of individual effects.

IGF-1 Axis Stimulation

Through its effects on GH release, ipamorelin indirectly stimulates hepatic production of insulin-like growth factor 1 (IGF-1), which mediates many of the downstream anabolic and metabolic effects attributed to the GH/IGF-1 axis. This includes effects on protein synthesis, muscle metabolism, bone formation, and lipid metabolism.

Research Applications

Growth Hormone Physiology Research

Ipamorelin is a primary tool compound for studying GH secretion, pulsatility, and the GHS-R1a signaling pathway. Its selectivity allows researchers to investigate GH-specific effects without confounding variables from other pituitary hormones.

Body Composition Research

Research has examined ipamorelin’s effects on body composition, including lean mass accretion, fat mass reduction, and metabolic rate modulation. Its GH-stimulatory effects drive changes in protein synthesis, lipolysis, and energy expenditure that are of interest in body composition research.

Bone Metabolism Research

Ipamorelin has been studied in models of bone metabolism and osteoporosis. GH and IGF-1 are critical regulators of bone formation and remodeling, and ipamorelin’s ability to stimulate the GH/IGF-1 axis has been examined in the context of bone mineral density, osteoblast activity, and fracture healing. Svensson et al. (2000) studied ipamorelin effects on bone markers in clinical research settings (PMID: 10997609).

Post-Surgical Recovery Research

Research has investigated ipamorelin in post-operative recovery models, where GH stimulation may accelerate tissue repair, reduce catabolism, and improve functional recovery. Clinical studies have examined its effects on gastrointestinal recovery following bowel surgery.

GHS-R1a Pharmacology Research

Ipamorelin serves as a selective GHS-R1a agonist tool compound for pharmacological studies examining ghrelin receptor signaling, receptor desensitization, and structure-activity relationships within the GHS class.

Available Formats and Bulk Options

• Standard Research Vials: 2 mg and 5 mg lyophilized powder per vial
• High-Volume Vials: 10 mg per vial
• Bulk Lyophilized Powder: 50 mg, 100 mg, 500 mg, and 1 g quantities
• Custom Formulations: Available upon request

Wholesale Pricing Summary

For detailed pricing, visit our wholesale pricing page or contact our B2B team.

Quality, Testing, and Certificates of Analysis

• HPLC Purity: RP-HPLC confirms ≥99% purity.
• Mass Spectrometry: ESI-MS confirms molecular weight of 711.85 g/mol and structural identity.
• Amino Acid Analysis: Confirms correct pentapeptide composition including non-natural amino acids.
• Chiral Purity: Verification of D-amino acid configurations (D-2-Nal, D-Phe).
• Endotoxin Testing: LAL assay <1 EU/mg.
• Sterility Testing: Per USP standards for in vivo-grade presentations.

Storage and Stability

Lyophilized Form

• Long-term: -20°C, protected from light. Shelf life 24+ months.
• Short-term: 2-8°C for up to 3 months.
• Room temperature: Stable for up to 2 weeks at 20-25°C.

Reconstituted Solution

• Vehicle: Bacteriostatic water or sterile 0.9% NaCl.
• Storage: 2-8°C for up to 14 days; aliquot and freeze at -20°C for up to 3 months.

Compliance and Intended Use

Research Use Only (RUO). Ipamorelin supplied by Wholesale Bulk Peptides is intended solely for in vitro and preclinical research by qualified investigators. This product is not intended for human or veterinary diagnostic or therapeutic use. Ipamorelin has not been approved by the FDA or any regulatory authority for any clinical indication.

Purchasers assume full responsibility for compliance with all applicable regulations.

Related Compounds

• CJC-1295 — A GHRH analog frequently studied in combination with ipamorelin for synergistic GH release through complementary receptor mechanisms.
• BPC-157 — A cytoprotective peptide studied in tissue repair models where GH-mediated pathways are relevant.
• TB-500 — Thymosin Beta-4 fragment studied in tissue repair research.

References

1. Raun K, Hansen BS, Johansen NL, et al. Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol. 1998;139(5):552-561. PMID: 9849822
2. Anderson LL, Jeftinija S, Scanes CG. Growth hormone secretion: molecular and cellular mechanisms and in vivo approaches. Exp Biol Med. 2004;229(4):291-302. PMID: 15044711
3. Svensson J, Lall S, Dickson SL, et al. The GH secretagogues ipamorelin and GH-releasing peptide-6 increase bone mineral content in adult female rats. J Endocrinol. 2000;165(3):569-577. PMID: 10828840
4. Johansen PB, Nowak J, Skjaerbaek C, et al. Ipamorelin, a new growth-hormone-releasing peptide, induces longitudinal bone growth in rats. Growth Horm IGF Res. 1999;9(2):106-113. PMID: 10373343
5. Beck DE, Sweeney WB, McCarter MD, et al. Prospective, randomized, controlled, proof-of-concept study of the Ghrelin mimetic ipamorelin for the management of postoperative ileus in bowel resection patients. Int J Colorectal Dis. 2014;29(12):1527-1534. PMID: 25266785

Frequently Asked Questions

What is ipamorelin?

Ipamorelin is a synthetic pentapeptide growth hormone secretagogue that selectively stimulates GH release through GHS-R1a (ghrelin receptor) activation. It is distinguished by its selectivity for GH over other pituitary hormones.

What makes ipamorelin selective?

Unlike other GHS-R1a agonists such as GHRP-6, ipamorelin stimulates GH release at doses that do not significantly affect ACTH, cortisol, prolactin, or other pituitary hormones. This selectivity is attributed to its specific binding orientation within the GHS-R1a receptor.

What purity is guaranteed?

All ipamorelin is supplied at 99%+ purity by RP-HPLC with MS identity, amino acid analysis, chiral purity verification of D-amino acids, endotoxin testing, and sterility testing.

How should ipamorelin be stored?

Lyophilized at -20C (24+ months stability) or 2-8C short-term (3 months). Reconstituted in bacteriostatic water at 2-8C for up to 14 days or aliquot and freeze at -20C.

Why is ipamorelin often studied with CJC-1295?

Ipamorelin (GHS-R1a/Gq pathway) and CJC-1295 (GHRH-R/Gs pathway) activate complementary intracellular signaling cascades, producing synergistic GH release that exceeds the sum of individual effects. This combination is one of the most commonly studied GH stimulation protocols.

What is the minimum order quantity?

Wholesale orders begin at 10 vials (5 mg each). Volume discounts from 12% to 45% are available, with custom pricing for orders exceeding 1,000 vials.

Is ipamorelin FDA-approved?

No. Ipamorelin is a Research Use Only compound. It has not been approved by the FDA or any regulatory authority for human or veterinary use.

What research areas use ipamorelin?

GH physiology, body composition, bone metabolism, post-surgical recovery, GHS-R1a pharmacology, and GH/IGF-1 axis research. It serves as the reference selective GHS in growth hormone research.

Does ipamorelin affect appetite?

While GHS-R1a is the ghrelin receptor (involved in appetite regulation), ipamorelin’s selectivity profile results in minimal appetite stimulation compared to ghrelin itself or less selective GHS-R1a agonists like GHRP-6.

What documentation is provided?

Batch-specific COA with HPLC purity, MS identity, amino acid analysis, chiral purity, endotoxin, and appearance data. SDS available upon request.

What is the lead time?

Standard orders ship within 3-5 business days. Bulk powder orders may require 7-10 business days. Expedited processing available.

Is bulk powder available?

Yes. Available in 50 mg, 100 mg, 500 mg, and 1 g bulk quantities in addition to standard 2 mg, 5 mg, and 10 mg vials.