Sermorelin

Description

Sermorelin, also designated as GHRH(1-29)NH2, is a synthetic 29-amino-acid peptide that corresponds to the first 29 residues of the naturally occurring 44-amino-acid growth hormone-releasing hormone (GHRH) produced by the hypothalamus. This truncated analogue retains the full biological activity of endogenous GHRH, as research has established that the first 29 amino acids constitute the minimal sequence required for complete receptor binding and activation of the GHRH receptor (GHRH-R) on anterior pituitary somatotroph cells. Sermorelin is the most extensively studied growth hormone secretagogue in the research literature, with decades of published data spanning from receptor pharmacology to in vivo secretion dynamics.

The mechanism of action centers on the selective binding of Sermorelin to the GHRH receptor, a G-protein coupled receptor that activates adenylyl cyclase and elevates intracellular cAMP levels in pituitary somatotrophs. This cAMP-dependent signaling cascade triggers both the synthesis and the pulsatile release of growth hormone (GH) from secretory granules. A critical distinction between Sermorelin and exogenous GH administration is that Sermorelin preserves the physiological pulsatile pattern of GH secretion. In preclinical models, Sermorelin-stimulated GH release follows the natural ultradian rhythm, with amplified pulse peaks rather than the sustained supraphysiological elevation seen with direct GH injection. This pulsatile pattern is essential for maintaining GH receptor sensitivity and downstream IGF-1 signaling fidelity in experimental protocols.

Compared to full-length GHRH(1-44), Sermorelin offers practical advantages for research applications. The shorter peptide sequence is more cost-effective to synthesize, exhibits improved stability in solution, and demonstrates equivalent receptor affinity and efficacy in standardized bioassays. When compared to natural GHRH, Sermorelin shows comparable binding kinetics at the GHRH-R, with dissociation constants in the low nanomolar range documented across multiple receptor binding studies. The C-terminal amidation of the peptide further enhances its resistance to enzymatic degradation by carboxypeptidases, extending its functional half-life in experimental conditions.

Synergistic research protocols frequently combine Sermorelin with growth hormone-releasing peptides (GHRPs) such as Ipamorelin or GHRP-6, which act on the distinct ghrelin receptor (GHS-R1a). This dual-pathway stimulation produces significantly amplified GH pulse amplitudes compared to either class of secretagogue alone, a well-documented phenomenon in somatotropic axis research. Areas of active investigation include recovery and performance models examining GH-mediated tissue repair, body composition changes associated with sustained pulsatile GH elevation, and anti-aging research exploring the relationship between age-related GH decline and the responsiveness of the GHRH-GHRH-R axis to exogenous stimulation.

Sermorelin acetate is supplied as a white lyophilized powder with purity exceeding 98% as confirmed by HPLC analysis. Each vial contains 10mg of peptide and should be reconstituted with bacteriostatic water prior to use in research applications. The peptide sequence is Tyr-Ala-Asp-Ala-Ile-Phe-Thr-Asn-Ser-Tyr-Arg-Lys-Val-Leu-Gly-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Met-Ser-Arg-NH2.

EU Shipping: Ships from EU warehouse in 24-48h. Free shipping on orders over €100. No customs delays — intra-EU shipment. Tracked via Spring GDS / DHL EU Connect. Janoshik COA available per batch on request.

Reconstitution & Administration Protocol

Sermorelin 10mg is supplied as a sterile lyophilized powder for reconstitution with bacteriostatic water (0.9% benzyl alcohol). Standard laboratory protocols are summarized below — researchers should validate against their own internal SOPs.

• Recommended diluent: Bacteriostatic Water (BAC water) with 0.9% benzyl alcohol preservative.
• Standard dilution: Add 2 ml of BAC water to the 10mg vial → final concentration 5 mg/ml.
• Alternative dilution: Add 1 ml of BAC water → final concentration 10 mg/ml — preferred when smaller draw volumes are needed.
• Technique: Inject the diluent slowly along the inner wall of the vial. Do not aim directly at the powder bed. Swirl the vial gently for 30-60 seconds until fully dissolved. Never shake — vigorous agitation can fragment the 29-residue peptide chain.
• Expected appearance: Clear, colorless solution with no particulates.
• Typical research dosing window: 100-300 mcg per dosing event in rodent secretagogue studies. Pre-sleep timing is commonly used to align with endogenous GH pulse rhythm and avoid superimposing the dose on a natural GH wave.
• Typical draw volumes: At 5 mg/ml, 100 mcg = 20 μl draw on a precision insulin syringe; 300 mcg = 60 μl.
• Post-reconstitution stability: Store at 2-8°C protected from light. Use within 30 days; discard if solution becomes cloudy or develops particulates.

Stability & Half-Life Data

• Plasma half-life: Approximately 11-12 minutes following subcutaneous administration in rodent pharmacokinetic studies. Clearance occurs via rapid enzymatic degradation by dipeptidyl peptidase IV (DPP-IV) at the N-terminal Tyr-Ala bond and by serum endopeptidases.
• GH pulse profile: The short half-life produces a sharp, brief GH pulse 15-30 minutes post-injection, closely mimicking endogenous GHRH-mediated pulse dynamics — in contrast to long-acting GHRH analogs (CJC-1295 with DAC, ~8 day half-life) which produce continuous receptor activation.
• Lyophilized stability: Up to 24 months when stored at -20°C in a sealed vial protected from light and moisture. Up to 4 weeks at 2-8°C without measurable purity loss.
• Reconstituted stability: 30 days at 2-8°C in low-protein-binding polypropylene containers, protected from light. Beyond 30 days, oxidation of Met-27 and gradual N-terminal degradation may reduce biological activity.
• Thermal stability: Lyophilized form is stable up to 40°C for short transport excursions. Avoid sustained temperatures above 25°C.
• Freeze-thaw: Avoid repeated freeze-thaw cycles of reconstituted solution. Aliquot into single-use volumes before freezing if long-term storage is required.
• Incompatibilities: Avoid strong oxidizing agents — methionine-27 in the sequence is susceptible to oxidation to methionine sulfoxide, which reduces receptor affinity.

Composition

• Peptide: Sermorelin acetate (GHRH 1-29 NH2)
• Sequence: Tyr-Ala-Asp-Ala-Ile-Phe-Thr-Asn-Ser-Tyr-Arg-Lys-Val-Leu-Gly-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Met-Ser-Arg-NH2
• Molecular Formula: C149H246N44O42S
• Molecular Weight: 3357.93 g/mol
• Purity: >98% (HPLC)
• Appearance: White to off-white lyophilized powder
• Quantity: 10mg per vial

Storage

• Store lyophilized peptide at -20C for long-term storage (up to 24 months).
• For short-term storage (up to 4 weeks), refrigerate at 2-8C.
• After reconstitution, store at 2-8C and use within 30 days.
• Avoid repeated freeze-thaw cycles.
• Protect from light and moisture at all times.

Certificate of Analysis

Every batch of Sermorelin sold by Pepspan undergoes rigorous third-party testing. Our Certificate of Analysis (COA) includes HPLC purity analysis, mass spectrometry confirmation, endotoxin testing, and sterility verification. COA documentation is available upon request for any batch number. All testing is performed by independent European laboratories to ensure the highest standards of accuracy and reliability.

Current Batch: Pending first shipment

Every batch of Sermorelin sold by Pepspan is independently tested by Janoshik Analytical (Prague, Czech Republic). HPLC purity analysis, mass spectrometry, and amino acid sequencing are performed for each shipment. Reports are batch-specific — not generic.

Research Disclaimer

All products on this website are sold strictly for research purposes only. Not intended for human or animal consumption. Must be handled by qualified professionals. Keep out of reach of children. By purchasing, you confirm you are a qualified researcher and will use these products solely for scientific research. Sermorelin is not approved for human or veterinary use by any regulatory agency. It must not be administered to humans or animals outside of approved clinical trials. Pepspan assumes no liability for any misuse of this product. All handling must comply with local regulations and institutional safety protocols.

Further Research Resources

Additional research articles, comparison guides, and laboratory protocols related to this peptide:

• CJC-1295 + Ipamorelin growth-hormone research
• Epithalon longevity research in Europe
• How to reconstitute lyophilized peptides