Semax Peptide: Research Guide for Canadian Labs

Semax is a synthetic heptapeptide derived from the N-terminal fragment of adrenocorticotropic hormone (ACTH 4–7), with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Originally developed at the Institute of Molecular Genetics of the Russian Academy of Sciences, Semax has been studied extensively in preclinical models for neuroprotective, cognitive-enhancing, and anti-inflammatory properties.

Unlike ACTH itself, Semax does not stimulate cortisol secretion — its Pro-Gly-Pro extension eliminates adrenocortical activity while preserving and amplifying CNS effects.

Semax (Met-Glu-His-Phe-Pro-Gly-Pro) is a stabilized analogue of the ACTH 4–7 fragment. The Pro-Gly-Pro C-terminal extension protects the peptide from enzymatic degradation, extending its biological activity compared to the native ACTH fragment.

Molecular characteristics:

• Sequence: Met-Glu-His-Phe-Pro-Gly-Pro
• Molecular weight: 813.9 Da
• CAS number: 80714-61-0
• Derived from: ACTH 4–7 (Met-Glu-His-Phe)

Semax acts as an agonist at melanocortin receptors, particularly MC4R, which are expressed throughout the CNS. MC4R activation is associated with neuroprotective signalling, synaptic plasticity, and modulation of dopaminergic and serotonergic systems.

The most extensively documented mechanism of Semax is its upregulation of neurotrophic factors. Preclinical studies have demonstrated significant increases in:

• BDNF (Brain-Derived Neurotrophic Factor): Critical for neuronal survival, synaptic plasticity, and hippocampal neurogenesis
• NGF (Nerve Growth Factor): Important for cholinergic neuron maintenance and peripheral nerve regeneration
• VEGF (Vascular Endothelial Growth Factor): Implicated in angiogenesis and neuroprotection following ischemic injury

Semax has been shown to modulate dopamine and serotonin metabolism in the striatum and frontal cortex. Research suggests effects on dopamine receptor sensitivity and monoamine turnover, which may contribute to its cognitive and mood-related research profile.

Semax demonstrates anti-inflammatory properties in preclinical models, including reduction of pro-inflammatory cytokines (IL-1β, TNF-α) and attenuation of NF-κB signalling following ischemic or excitotoxic insult.

Research has examined Semax's effects on nitric oxide synthase (NOS) activity, with implications for cerebrovascular regulation and neuroprotection in ischemia models.

Semax has one of the strongest preclinical profiles among nootropic peptides for ischemic neuroprotection. Studies in rodent stroke models (middle cerebral artery occlusion) have demonstrated reductions in infarct volume, improved neurological scores, and enhanced recovery when Semax is administered in the acute post-ischemic period.

Rodent studies using Morris water maze, radial arm maze, and passive avoidance paradigms have demonstrated improvements in spatial memory, learning acquisition, and memory retention following Semax administration. BDNF upregulation in the hippocampus is the proposed primary mechanism.

Semax has been studied in models of optic nerve damage and glaucoma, where its neurotrophic and anti-apoptotic effects on retinal ganglion cells have been investigated.

Preclinical research has examined Semax in models of attention deficit and hyperactivity, with dopaminergic modulation proposed as the relevant mechanism.

Semax's anti-inflammatory properties have been studied in models of neuroinflammation, including lipopolysaccharide (LPS)-induced neuroinflammation and autoimmune encephalomyelitis models.

Semax is supplied as a lyophilized powder requiring reconstitution with bacteriostatic water (BAC water).

Suggested reconstitution:

• 5 mg vial + 1 mL BAC water → 5 mg/mL (5,000 mcg/mL)
• 10 mg vial + 2 mL BAC water → 5 mg/mL (5,000 mcg/mL)

For intranasal research applications, lower concentrations are typically used:

• 10 mg vial + 10 mL BAC water → 1 mg/mL (1,000 mcg/mL)

Use our Reconstitution Calculator for precise volume calculations. See our General Reconstitution Guide for sterile technique.

IN = intranasal. Semax has been extensively studied via intranasal delivery due to its ability to bypass the blood-brain barrier via the olfactory pathway, making it a useful model compound for CNS-targeted peptide delivery research.

Semax is relatively stable in solution compared to many peptides. Nonetheless, aliquoting is recommended for protocols requiring repeated use over extended periods.

For research requiring both neuroprotective and anxiolytic coverage, Semax and Selank are frequently studied in combination given their complementary mechanisms and both upregulating BDNF through different pathways.

Semax 10 mg is currently coming soon at Peptide-Labs. We are completing quality verification and third-party CoA testing before release. Join the waitlist to be notified when Semax becomes available.

Semax is intended solely for in vitro research and preclinical laboratory use. It is not approved for human consumption, veterinary use, or clinical application in Canada. All research must be conducted by qualified professionals in compliance with applicable regulations.