Hexarelin 5mg

Compound Name: Hexarelin

Synonyms: Examorelin, HEX, GHRP-6 analog

CAS Number: 140703-51-1

Molecular Formula: C₄₇H₅₈N₁₂O₆

Molecular Weight: 887.04 g/mol

Structure: Synthetic hexapeptide

Peptide Sequence: His-D-2-Me-Trp-Ala-Trp-D-Phe-Lys-NH₂

Chemical Structure:

Source: PubChem

Mechanism of Action: Hexarelin is a potent agonist at the ghrelin receptor (GHS-R1a). It stimulates growth hormone secretion through both pituitary and hypothalamic actions, independent of GHRH pathways. When co-administered with GHRH, Hexarelin exhibits synergistic GH-releasing effects. It also shows activity at peripheral GHS receptors, notably in cardiac tissue, contributing to GH-independent cardiotropic actions³.

Biological Activity: Hexarelin acts as a potent stimulator of growth hormone (GH) secretion by activating the ghrelin receptor (GHS-R1a) in both the pituitary and hypothalamus. It promotes the release of GH in a dose-dependent manner, leading to elevated circulating GH levels. In addition to its GH-releasing properties, Hexarelin exerts cardioprotective effects by enhancing cardiac contractility and supporting myocardial function, independent of its hormonal actions. It also contributes to skeletal health by reducing bone resorption and helping to maintain bone mineral density. Hexarelin exhibits a selective endocrine profile, mildly stimulating prolactin and cortisol secretion while having minimal impact on other hormones such as IGF-I, LH, FSH, and TSH^1,4.

Storage:

• Store at −20°C, protect from light and moisture.
• Reconstitute in sterile saline or PBS (pH ~7.4).
• Avoid repeated freeze-thaw cycles.

Drug Categories: Amino Acids, Peptides, and Proteins; Endocrine Modulators

Additional Notes:

• Improved stability over GHRP-6 due to methylation
• Used in models of GH deficiency, cardiovascular dysfunction, and osteoporosis
• Exhibits synergistic effects when co-administered with GHRH²
• Suitable for both in vitro and in vivo research applications

Summary Table:

Disclaimer: For Research Use Only. Not intended for human or veterinary use. This compound is supplied solely for laboratory and R&D purposes.

Detailed Product Description

Hexarelin is a synthetic hexapeptide designed to mimic the action of endogenous ghrelin by activating the growth hormone secretagogue receptor (GHS-R1a). Unlike GHRH, Hexarelin operates via a separate receptor system, stimulating growth hormone release through hypothalamic and pituitary pathways. The peptide has been chemically modified for enhanced metabolic stability, particularly through the methylation of D-tryptophan, which resists proteolytic degradation¹. Hexarelin has been investigated across diverse preclinical and clinical contexts for its ability to stimulate GH, modulate cardiac function, and influence skeletal remodeling. Its activity is short-acting but highly potent, characterized by rapid onset of GH release and quick systemic clearance. Beyond GH secretion, Hexarelin exerts direct effects on cardiac tissue by increasing left ventricular ejection fraction (LVEF) and improving myocardial performance. It also reduces bone resorption, making it a candidate for research on bone preservation in hormone-deficient states⁴.

Research Highlights

• Stimulates Endogenous GH Release: Binds to pituitary GHS-R1a receptors and rapidly induces growth hormone secretion through calcium-mediated exocytosis².
• Improves Cardiac Function: Increases cardiac output and left ventricular function independently of GH, likely through myocardial GHS-R1a activation³.
• Reduces Bone Resorption: Lowers bone turnover markers and helps preserve bone mineral density in androgen-deficient states⁴.
• Selective Hormonal Profile: Minimal effects on IGF-I, TSH, FSH, LH; modest increases in prolactin and cortisol levels¹.

Mechanism of Action

Hexarelin functions as a synthetic peptide agonist of the growth hormone secretagogue receptor type 1a (GHS-R1a), also known as the ghrelin receptor. By binding to this receptor in the hypothalamus and anterior pituitary, hexarelin stimulates the endogenous release of growth hormone (GH) through a pathway independent of GHRH. In doing so, it initiates downstream anabolic and metabolic processes traditionally linked to the GH–IGF-1 axis, while also exerting GH-independent effects in peripheral tissues such as the heart and bone^1-4.

1. GHS-R1a (Ghrelin Receptor) Agonism

• Stimulates pulsatile GH secretion: Hexarelin binds to GHS-R1a on pituitary somatotrophs, activating G-protein signaling pathways that mobilize intracellular calcium and stimulate GH exocytosis. This pathway is independent of the GHRH receptor and supports physiologic, feedback-regulated GH secretion^1,2.
• Synergizes with GHRH: When administered alongside GHRH, hexarelin produces an amplified GH response, indicating that the two act via complementary but distinct receptors².
• Enhances cardiac function: GHS-R1a is also expressed in myocardial tissue. Hexarelin activation of cardiac receptors improves left ventricular ejection fraction (LVEF) and myocardial contractility, independently of GH or IGF-1 levels³.
• Reduces bone resorption: Hexarelin exhibits bone-protective effects in androgen-deficient models, decreasing markers of bone resorption and preserving bone mineral density. These effects appear to result from direct receptor-mediated signaling in skeletal tissue⁴.
• Hexarelin has high-affinity for the GHS-R1a receptor (EC₅₀, Human ~0.39 nM)¹.

Pharmacokinetic Profile:

• Route of Administration: IV or SC (preclinical models)
• Dosing Frequency: Multiple daily or episodic
• Half-Life: GH response: ~55 minutes

Formulation & Handling

• Reconstitute in sterile saline or PBS (pH ~7.4) for in vivo/in vitro use
• Store at −20°C, protect from light and repeated freeze-thaw cycles

• Shelf-stable for 12 months under proper conditions

Clinical Trial Activity

Hexarelin is a research-grade compound that has been studied in laboratory and early-stage human settings but has not undergone full clinical development. It is not approved for therapeutic use in humans, and no large-scale clinical trials have been conducted to evaluate its safety or efficacy as a medication. Hexarelin is supplied strictly for laboratory research and investigational purposes only.

References

¹Ghigo, E. et al. Growth hormone-releasing activity of hexarelin, a new synthetic hexapeptide, in man. Eur. J. Endocrinol. 133, 448–454 (1995).

²Ciccarelli, E. et al. Hexarelin, a synthetic growth hormone releasing peptide, stimulates growth hormone secretion in normal men and acts synergistically with growth hormone releasing hormone. Clin. Endocrinol. 44, 601–606 (1996).

³Bisi, G. et al. Cardiovascular effects of hexarelin in humans. J. Endocrinol. Invest. 25, RC11–RC14 (2002).

⁴Locatelli, V. et al. Growth hormone-independent cardioprotective effects of hexarelin in the rat. Life Sci. 58, PL287–PL294 (1996).