Skip to content

Sermorelin

Sermorelin (CAS 86168-78-7) is a synthetic 29-amino acid peptide corresponding to the N-terminal biologically active fragment of growth hormone-releasing hormone (GHRH 1–29), with a molecular weight of 3,358.0 Da and formula C₁₄₉H₂₄₆N₄₄O₄₂S. As the first FDA-available GHRH analog, sermorelin represents the minimal GHRH sequence that retains full receptor binding and activation capacity. It is a foundational research tool in growth hormone neuroendocrinology, pulsatile GH secretion studies, and hypothalamic-pituitary axis pharmacology.

Technical Specifications

Property Value
CAS Number 86168-78-7
Molecular Formula C₁₄₉H₂₄₆N₄₄O₄₂S
Molecular Weight 3,358.0 Da
Purity ≥98% (HPLC-verified)
Appearance Lyophilized white powder
Solubility Soluble in sterile water and aqueous buffers
Storage -20°C (lyophilized), 2–8°C (reconstituted)

Mechanism of Action

Sermorelin is the 1–29 N-terminal fragment of GHRH (also termed GRF 1–29), which contains the full receptor-binding domain and agonist pharmacophore. It binds the GHRH receptor (GHRH-R) on anterior pituitary somatotrophs, a class B GPCR, activating Gαs to stimulate adenylyl cyclase, elevate intracellular cAMP, and activate PKA. PKA-mediated phosphorylation of L-type calcium channels promotes calcium influx, triggering GH secretory vesicle exocytosis in a pulsatile pattern. Because sermorelin lacks the C-terminal 30–44 amino acid sequence, it has a shorter plasma half-life (~10–12 minutes) than full-length GHRH or tesamorelin. Critically, sermorelin preserves the physiological GH negative feedback loop: GH-induced hepatic IGF-1 production feeds back to the hypothalamus to increase somatostatin tone and suppress further GHRH secretion, maintaining pulsatile rather than continuous GH output. This preservation of physiological regulation distinguishes GHRH analogs from ghrelin mimetics, which bypass somatostatin feedback.

Research Applications

  • Primary: GHRH receptor pharmacology — pituitary somatotroph signaling, pulsatile GH secretion dynamics
  • Secondary: Pediatric growth endocrinology models, IGF-1 axis regulation, neuroendocrine aging studies
  • Model Systems: In vitro (dispersed rat pituitary cells, GHRH-R binding assays), in vivo (GH pulsatility studies, hypophysiotropic hormone feedback models)

Quality Control & Analytical Methods

  • HPLC: ≥98% purity verification at 214/220 nm (C18 reversed-phase column)
  • Mass Spectrometry: ESI-MS for molecular weight confirmation (3,358.0 ±1.0 Da)
  • Peptide Content: Amino acid analysis (AAA) for net peptide content determination
  • Endotoxin: <1 EU/mg (LAL assay)
  • TFA Content: <1% (ion chromatography)

Stability & Storage

Condition Stability
-20°C (lyophilized) 24 months
4°C (lyophilized) 6 months
25°C (lyophilized) 1 month
Reconstituted (4°C) 7 days
Reconstituted (-20°C) 30 days

Key Research References

  • Thorner et al. (1983) — GRF 1-29: biological activity and clinical applications. J Clin Endocrinol Metab. PMID: 6408113
  • Frohman et al. (1989) — Growth hormone-releasing hormone. Endocr Rev. PMID: 2508661
  • Gelato et al. (1985) — Effects of a growth hormone releasing factor in man. J Clin Endocrinol Metab. PMID: 3936563

Source & Purchase

For researchers requiring research-grade SERMORELIN with full analytical documentation including HPLC, LC-MS, and Certificate of Analysis, visit the HK Peptides product page for specifications, bulk pricing, and ordering.

View SERMORELIN Product →

FAQ

Q: What purity level is standard for Sermorelin? A: HK Peptides supplies Sermorelin at ≥98% purity by HPLC with full COA documentation.

Q: How should Sermorelin be stored for research use? A: Lyophilized Sermorelin should be stored at -20°C. Reconstituted solutions at 4°C for short-term use (up to 7 days).