Sermorelin

Sermorelin (GHRH 1-29 NH2) is a synthetic peptide analog consisting of the first 29 amino acids of the naturally occurring 44-amino-acid Growth Hormone Releasing Hormone (GHRH). This truncated form retains full biological activity, as the first 29 amino acids contain all the structural elements necessary for GHRH receptor binding and activation. Sermorelin was one of the first GHRH analogs developed for research use and remains widely studied for its ability to stimulate physiological growth hormone release.

The mechanism of action involves binding to the GHRH receptor (GHRHR) on somatotropic cells of the anterior pituitary gland. GHRHR is a class B G-protein coupled receptor that, upon activation, stimulates adenylyl cyclase through Gαs coupling, increasing intracellular cAMP levels. This activates protein kinase A (PKA), which phosphorylates CREB transcription factor, ultimately enhancing GH gene transcription and GH protein synthesis. Additionally, the cAMP/PKA pathway opens voltage-gated calcium channels, promoting exocytosis of GH-containing secretory granules.

A key characteristic distinguishing sermorelin from direct GH administration is the preservation of negative feedback regulation. Since sermorelin stimulates the pituitary to produce its own GH, the normal feedback loops involving somatostatin, IGF-1, and GH itself remain intact. This means GH release occurs in physiological pulses rather than the non-physiological sustained elevation seen with exogenous GH - an important consideration for research studying normal GH physiology.

Age-related research is a primary application, as GHRH responsiveness changes with aging. Studies using sermorelin have characterized the age-dependent decline in GH pulse amplitude (but not frequency), the role of increased somatostatin tone in somatopause, and the potential for restoring more youthful GH secretion patterns in older subjects.

Sleep research has documented that sermorelin enhances slow-wave sleep, the sleep stage most closely associated with GH secretion. This bidirectional relationship between GH and sleep architecture makes sermorelin valuable for studying sleep-endocrine interactions.

Body composition research has explored sermorelin's effects on lean mass, fat mass, and bone density through its downstream effects on the GH-IGF-1 axis.

For reconstitution, dissolve in bacteriostatic water using sterile technique. Store at 2-8°C and use within 4 weeks.

PeptidesDirect sermorelin is verified at ≥98% purity. Certificate of Analysis included. EU-shipped.