Semax Research Overview: The ACTH(4-10)-Derived Heptapeptide
Written from the cited peer-reviewed literature; every product lot is third-party tested.
For research purposes only. This content is intended for educational and informational purposes. Products mentioned are sold strictly for laboratory research use. Not for human consumption. Not for human use. Read more
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its first four amino acids come from adrenocorticotropic hormone (ACTH), and the added Pro-Gly-Pro sequence makes it more resistant to enzymatic breakdown.
This overview covers the ACTH fragment research Semax grew out of, how it was designed, the laboratory models it has been studied in, and the limits of its literature.
Background: ACTH fragments
ACTH is a 39-amino-acid hormone best known for stimulating the adrenal gland. In the 1960s and 1970s, research led by David de Wied in the Netherlands found that short fragments of ACTH, without the hormone's adrenal activity, still produced measurable effects in rodent behaviour studies. The fragment ACTH(4-10), Met-Glu-His-Phe-Arg-Trp-Gly, became a focus of that work.
The problem with these fragments was stability: short natural peptides break down within minutes.
How Semax was designed
Semax was developed at the Russian Academy of Sciences as a more stable analog in the ACTH(4-10) line. It keeps the first four residues of that fragment (Met-Glu-His-Phe) and replaces the rest with Pro-Gly-Pro, a proline-rich sequence that resists enzymatic breakdown. The same strategy was used for Selank. Our Selank research overview covers it in more detail.
A modified version, N-Acetyl Semax Amidate, adds an acetyl group at the N-terminus and an amide at the C-terminus. It is a different compound from standard Semax, so researchers should confirm which one they have from the certificate of analysis. Our Semax is the standard, unmodified heptapeptide.
Laboratory models
Preclinical research on Semax includes:
- Rodent models of cerebral ischemia, one of the earliest and most studied areas
- Expression of brain-derived neurotrophic factor (BDNF) and its receptor TrkB in rat brain tissue
- Gene expression studies in brain tissue under experimental conditions
- Rodent behaviour studies building on the earlier ACTH fragment research
Results in rodent models do not establish activity in other systems.
Limits of the literature
Most published research on Semax comes from Russian research groups, often the same institutions that developed it, and a significant share appears in Russian-language journals. Much of it has not been independently replicated by groups outside Russia. Researchers should review the primary literature directly and weigh it with that context in mind.
Handling in the laboratory
Semax is supplied as a lyophilized powder and is generally reconstituted with bacteriostatic water before use. Sealed vials are stored at -20°C, protected from light and moisture.
Testing and documentation
Every lot we sell is tested by Freedom Diagnostics, an independent laboratory, using HPLC for purity and mass spectrometry for identity. Certificates are published in our COA library, and each can be verified directly with the lab using the search code printed on it. Our guide explains how to verify a COA.
Every lot is third-party tested. View the certificate for Semax →
Related reading
For research purposes only. All products from Canada Research Labs are supplied strictly as reference materials for in-vitro laboratory research by qualified professionals. They are not drugs, natural health products or cosmetics, and have not been authorized by Health Canada for any human or veterinary use.
