Sermorelin Acetate: Scientific Profile

Publicado el 12 de julio de 2026 · Actualizado el 17 de agosto de 2026

Sermorelin Acetate (CAS 86168-78-7) is a synthetic 29-amino-acid peptide that reproduces the biologically active N-terminal fragment of growth hormone-releasing hormone (GHRH 1-29). It acts as a growth hormone secretagogue by directly stimulating GHRH receptors in the pituitary. It is offered exclusively for research use.

Sermorelin Acetate is the acetate salt of sermorelin, a synthetic peptide of 29 amino acids that corresponds to the amino-terminal fragment (residues 1-29) of human growth hormone-releasing hormone (GHRH, also called somatoliberin or growth hormone-releasing factor, GRF). Its chemical identity is well established: molecular formula C149H246N44O42S, approximate molecular weight of 3357.93 g/mol, and CAS number 86168-78-7. The usual synonyms in the literature are GRF (1-29) NH2 and GHRH (1-29) amide. The interest of this fragment lies in the fact that the 1-29 portion retains practically the entire biological activity of the native GHRH molecule, which has 44 amino acids; residues 30-44 are not necessary for receptor binding or for the activation of signaling, so sermorelin represents the minimal functional unit of the endogenous peptide.

From a structural standpoint, sermorelin is a linear peptide with an amidated carboxyl terminus, a modification that contributes to its recognition by the receptor. The sequence begins with tyrosine at position 1, a residue critical for activity, and contains the recognition motifs that interact with the GHRH receptor. Like many small peptides, the native molecule is susceptible to degradation by the enzyme dipeptidyl peptidase-4 (DPP-4), which cleaves the bond between the first two residues, which explains the short plasma half-life observed in models and the basis for the numerous analog modifications developed subsequently (for example, tesamorelin and CJC-1295) to prolong its action.

The mechanism of action of sermorelin is that of a growth hormone secretagogue that acts upstream, at the pituitary level. It binds to the GHRH receptor (GHRHR), a G protein-coupled receptor of the secretin family expressed in the somatotroph cells of the anterior pituitary. Activation of the receptor stimulates adenylate cyclase, increases intracellular cyclic AMP, and activates protein kinase A, which promotes both the synthesis and the pulsatile release of endogenous growth hormone (GH). Unlike the exogenous administration of recombinant GH, this mechanism acts on the organism's physiological machinery, so in models it preserves the negative feedback mechanisms: secretion remains subject to the control of somatostatin and to feedback inhibition by insulin-like growth factor 1 (IGF-1). This feature has been one of the central arguments in research on the use of sermorelin versus direct GH, since it theoretically reduces the risk of sustained supraphysiological exposure.

Unlike most less-characterized research peptides, sermorelin has a substantial body of clinical evidence. It was developed and studied during the 1980s and 1990s, and came to be marketed as an approved drug, with applications in the assessment of pituitary somatotropic function and in the study of growth hormone deficiency in pediatric populations. In this context its ability to elicit a measurable elevation in GH following administration was characterized, which gave rise to its use as an agent in stimulation tests designed to distinguish pituitary-origin deficiency from other causes. The original product was subsequently withdrawn from the market for commercial reasons and not for safety concerns, and the compound has remained an object of interest in research on the GHRH-GH-IGF-1 axis.

The documented research applications focus on several axes. First, sermorelin is used as a pharmacological tool to probe the integrity and reactivity of the somatotropic axis, that is, to evaluate whether the pituitary retains the capacity to respond to a GHRH stimulus. Second, it has been used in studies on the pulsatile architecture of GH secretion and on how this is modified with age, given that the amplitude of GH pulses declines in aging (somatopause); research models have explored whether stimulation with secretagogues such as sermorelin can restore more youthful secretion patterns. Third, it is investigated in the context of states associated with low GH production, including models of body composition, metabolism, and studies on sleep quality, since there is a known relationship between GH secretion and slow-wave sleep phases.

As for the level of evidence, sermorelin occupies a relatively solid position among research peptides: there is peer-reviewed clinical literature documenting its pharmacology and its GH-stimulating capacity, and its identity and mechanism are well known. Nonetheless, much of the clinical evidence comes from studies of the 1980s-1990s and from specific populations, and long-acting analogs have largely displaced sermorelin in the more recent lines of research. For this reason, any interpretation of the data must remain within a research framework, recognizing that the characterization, though robust for a peptide of this type, does not amount to an endorsement for applications outside the laboratory.