Sermorelin: A Research Compound Overview

Sermorelin (GHRH 1-29): A Research Overview

Sermorelin is a synthetic analogue of human growth hormone-releasing hormone (GHRH) comprising the first 29 amino acids of the 44-residue native sequence. It is the shortest fully active fragment of GHRH and retains the complete biological activity of the full-length hormone at the GHRH receptor. Originally developed for diagnostic assessment of pituitary GH reserve, Sermorelin has been studied extensively in models of GH axis regulation and sleep architecture.

Research Applications

• GHRH receptor (GHRHR) binding kinetics and downstream cAMP signaling studies
• Pituitary somatotroph stimulation and GH pulse initiation models
• IGF-1 upregulation through the liver-pituitary axis
• Sleep architecture and slow-wave sleep enhancement research
• Pituitary reserve assessment in GH-deficient animal models
• Synergistic GH release in combination with GHSR agonists (Ipamorelin, GHRP-6, MK-677)
• Age-related GH axis decline and somatopause biology

Molecular Profile

• 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 Weight: 3357.9 Da
• CAS Number: 86168-78-7
• Half-life: ~10–20 minutes in plasma (DPP-IV sensitive)
• Format (Official Peptides): Lyophilized powder, >99% HPLC

Mechanism of Action

Sermorelin binds to the GHRH receptor on pituitary somatotrophs, activating adenylyl cyclase via Gαs and increasing intracellular cAMP. This stimulates both GH synthesis (via CREB phosphorylation) and GH secretion. Unlike direct GH administration, Sermorelin preserves the natural pulsatile pattern of GH release and maintains negative feedback sensitivity. The N-terminal tyrosine residue (Tyr¹) is critical for receptor binding; modifications at this position significantly reduce potency.

Research Considerations

Sermorelin is susceptible to DPP-IV cleavage at the Tyr-Ala bond. For in vitro receptor binding studies this is not an issue, but for cell-based secretion assays fresh preparation is recommended. Sermorelin shows additive to synergistic GH release when co-administered with GHSR agonists (GHRP-2, Ipamorelin, MK-677) due to complementary receptor signaling pathways.

For in vitro laboratory research only. Not for human consumption. Not FDA approved.