Research Reference · Two-Peptide Blend
Selank + Sermorelin (Blend)
A two-peptide research blend — Selank, a tuftsin-based peptide studied for stress signaling, and Sermorelin, the active 29-amino-acid part of GHRH — 5 mg of each in one vial.
At a glance
Selank + Sermorelin pairs two peptides from different families. Selank is a seven-amino-acid peptide built on tuftsin and studied for GABA, enkephalin and immune signaling. Sermorelin is the first 29 amino acids of growth-hormone-releasing hormone (GHRH) and was once an FDA-approved medicine (Geref). Our vials hold 5 mg of each (10 mg in total), and each batch certificate measures both. No study of the combination has been published; the evidence belongs to each peptide.
What it’s studied for
Enkephalin breakdown (Selank)
Slowed the enzymes that break down enkephalins in human plasma samples. 2
Test-tubeGrowth-hormone release (Sermorelin)
The 29-amino-acid fragment kept about half the full hormone’s potency in pituitary cells. 4
CellOlder men (Sermorelin)
Two weeks of treatment raised growth hormone and IGF-1 to young-adult levels in one study. 5
HumanSelank + Sermorelin
Selank + Sermorelin (10mg) · $49.99
Third-party tested · batch-matched COA · research use only
How it works
The blend combines two peptides with unrelated mechanisms. Selank is a seven-amino-acid peptide: tuftsin (Thr-Lys-Pro-Arg), a natural immune peptide, with a Pro-Gly-Pro tail added for stability. In rats it changed the activity of GABA-related signaling genes, 1 in human plasma samples it slowed the enzymes that break down enkephalins, 2 and in mouse spleen it shifted inflammation-related genes. 3
Sermorelin is the first 29 amino acids of growth-hormone-releasing hormone, with an amide at the end. It signals the pituitary to release the body’s own growth hormone; in a 1984 cell study the fragment kept about half the potency of the full 44-amino-acid hormone. 4 In healthy older men, two weeks of treatment raised growth hormone and IGF-1 to young-adult levels in one study, 5 and a review described it as a rapid, relatively specific test of pituitary growth-hormone release. 6
No study of the two together has been published, so each peptide’s evidence should be read on its own terms.
Related research
Frequently asked questions
What is in the blend?
What is Selank?
What is Sermorelin?
Has the blend itself been studied?
How is each batch verified?
Identifiers
| Components | Selank (5 mg) + Sermorelin (5 mg) |
|---|---|
| Total peptide | 10 mg per vial |
| Selank | Thr-Lys-Pro-Arg-Pro-Gly-Pro · C33H57N11O9 · CAS 129954-34-3 · PubChem CID 11765600 |
| Sermorelin | GHRH(1-29)NH2 · C149H246N44O42S · CAS 86168-78-7 · PubChem CID 16132413 |
| Supplied as | Lyophilized (freeze-dried) powder |
Component identifiers checked against PubChem (see the Selank and Sermorelin pages).
Research timeline
- 1984The 29-amino-acid fragment of GHRH (sermorelin) keeps about half the full hormone’s potency. 4
- 1992Sermorelin raises growth hormone and IGF-1 in older men to young-adult levels. 5
- 1999Review of sermorelin as a pituitary test. 6
- 2001Selank slows enkephalin-degrading enzymes in human plasma. 2
- 2014Selank shifts inflammation-related genes in mouse spleen. 3
- 2016Selank changes GABA-related gene activity in rat brain. 1
Key studies
| Study | Model | What it found |
|---|---|---|
| Volkova 2016 1 | Rat (Selank) | 45 signaling genes changed at 1 hour and 22 at 3 hours; the pattern correlated with GABA. |
| Zozulya 2001 2 | Human plasma, test tube (Selank) | Slowed enkephalin breakdown, more strongly than the enzyme blockers bacitracin and puromycin. |
| Ling 1984 4 | Rat pituitary cells (Sermorelin) | The hGRF(1-29)NH2 fragment kept about 50% of the full hormone’s growth-hormone-releasing potency. |
| Corpas 1992 5 | Human · older men (Sermorelin) | At the higher dose, 14 days of treatment raised 24-hour GH and IGF-1 to young-adult levels. |
Sources
- Selank Administration Affects the Expression of Some Genes Involved in GABAergic Neurotransmission. Volkova A, et al. Front Pharmacol, 2016. Free full text
- The inhibitory effect of Selank on enkephalin-degrading enzymes as a possible mechanism of its anxiolytic activity. Zozulya AA, et al. Bull Exp Biol Med, 2001.
- The temporary dynamics of inflammation-related genes expression under tuftsin analog Selank action. Kolomin T, et al. Mol Immunol, 2014.
- Synthesis and in vitro bioactivity of C-terminal deleted analogs of human growth hormone-releasing factor. Ling N, et al. Biochem Biophys Res Commun, 1984.
- Growth hormone (GH)-releasing hormone-(1-29) twice daily reverses the decreased GH and insulin-like growth factor-I levels in old men. Corpas E, et al. J Clin Endocrinol Metab, 1992. Human
- Sermorelin: a review of its use in the diagnosis and treatment of children with idiopathic growth hormone deficiency. Prakash A, Goa KL. BioDrugs, 1999. Review
Last reviewed November 2026 by Midwest Compounds. Every source above was checked against its original publication.