Introduction: The Russian Neuropeptides

Selank and Semax represent two of the most extensively studied neuropeptides in the AXON line — Rainbow Peptide’s cognitive and nootropic research category. Both compounds were developed by the Institute of Molecular Genetics of the Russian Academy of Sciences in the 1980s and 1990s, and both have been subjects of human pharmacological research (though not FDA-approved).

Selank: Research Overview

What Is Selank?

Selank (TP-7) is a synthetic heptapeptide analog of the endogenous human tetrapeptide tuftsin (Thr-Lys-Pro-Arg). Its sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, with the C-terminal Pro-Gly-Pro extension added by Russian researchers to improve metabolic stability.

Mechanism and Research Findings

Research has characterized Selank as an anxiolytic peptide with a profile distinct from benzodiazepines. Key findings from laboratory and early-stage research include:

  • Modulation of GABA-A receptor sensitivity without direct binding (indirect benzodiazepine-site activity)
  • Increased expression of BDNF (Brain-Derived Neurotrophic Factor) in hippocampal cell models
  • Anti-inflammatory activity through IL-6 and other cytokine pathways
  • Stable serotonin and dopamine transporter levels compared to classical anxiolytics, suggesting a preserved cognitive profile in animal models

Semax: Research Overview

What Is Semax?

Semax is a synthetic heptapeptide (Met-Glu-His-Phe-Pro-Gly-Pro) — a modified analog of the adrenocorticotropic hormone (ACTH) fragment 4–7. It was developed to capture the neurotrophic properties of ACTH without its hormonal activities. Semax is listed as an essential medicine in Russia.

Mechanism and Research Findings

Semax’s primary studied mechanism is BDNF and NGF (nerve growth factor) upregulation, which has produced interest in neuroprotection and cognitive research models. Additional findings include:

  • Increased expression of genes associated with neuronal plasticity (c-fos, BDNF, trkB)
  • Protective effects in rodent models of stroke and ischemia — one of the most published areas of Semax research
  • Dopaminergic system modulation in prefrontal cortex models
  • Enhanced long-term potentiation (LTP) in hippocampal slice preparations — a standard model for learning and memory research

Selank vs Semax: Research Comparison

Attribute Selank Semax
Source peptide Tuftsin analog ACTH 4-7 analog
Primary research area Anxiety models, immune Neuroprotection, cognition
Primary mechanism GABA modulation, BDNF BDNF/NGF upregulation
Rainbow Peptide dosage 10mg vial 25mg vial
Sub-line AXON AXON

Specifications

Both Selank and Semax are available as Tier 1 AXON-line compounds at Rainbow Peptide, supplied as lyophilized powder with >98% HPLC purity and batch-specific COA documentation.