Selank 5 mg

What Is Selank?

Selank is a synthetic research peptide classified as a heptapeptide (seven amino acids) with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It is a modified analogue of the naturally occurring human tetrapeptide tuftsin, which is involved in immune modulation.

Selank was originally developed by researchers at the Institute of Molecular Genetics (Russian Academy of Sciences) for investigation into its potential neuropsychotropic effects in preclinical models.

Selank is structurally designed to be more stable than endogenous neuropeptides. It resists rapid enzymatic degradation, making it well-suited for in vitro and animal-based studies. Its solubility in sterile water or buffered saline allows for consistent preparation in laboratory settings.

These properties enhance its reliability in research exploring mood regulation, learning, memory, and stress response pathways.

Please note: Evolve Peptides only sells Selank for research use. Not for human consumption, injection, or diagnostic purposes.

Researchers have studied Selank’s interaction with the GABAergic system, as well as its possible influence on cytokine expression, neurotransmitter balance, and neuroplasticity, though all findings remain within non-clinical, investigational contexts.

Selank Mechanism of Action (Based on Research)

Selank is a synthetic peptide with anxiolytic and nootropic effects. Research suggests it works by modulating neurotransmitters—especially GABA, serotonin, and dopamine—while also influencing immune and inflammatory pathways. Its mechanism resembles that of benzodiazepines but without sedation or dependency risks.

Allosteric Modulation of GABAA Receptors

Selank acts as a positive allosteric modulator of the GABAA receptor. In rodent studies, intranasal administration affected the binding of [³H]GABA and [³H]diazepam to these receptors, suggesting interaction at or near classic benzodiazepine sites without direct agonism.

In other words, intranasal Selank alters the binding of radiolabeled GABA and diazepam at GABAA receptors, suggesting it interacts allosterically at benzodiazepine sites—modulating the receptor rather than acting as a direct agonist.

One study showed that Selank significantly alters the expression of 45 genes linked to GABAergic neurotransmission in rat frontal cortex, with a strong correlation to GABA’s effects.

These findings reveal that Selank likely modulates GABAA receptor function at both binding and genetic levels, reinforcing the mechanism of allosteric modulation inferred from binding studies. [1].

Allosteric Modulation of GABAA Receptors

Selank acts as a positive allosteric modulator of the GABAA  receptor. In rodent studies, intranasal administration affected the binding of [³H]GABA and [³H]diazepam to these receptors, suggesting interaction at or near classic benzodiazepine sites without direct agonism [1].

This modulation can enhance inhibitory neurotransmission, contributing to anxiolytic effects.

Gene Expression Regulation in Neurotransmission Pathways

Selank’s influence extends beyond receptor-level interactions to the genetic regulation of key neurotransmission pathways. Emerging evidence shows that this peptide rapidly modulates the expression of genes linked to synaptic signaling, particularly those involved in GABA, dopamine, and serotonin systems.

In one study involving Wistar rats, Selank significantly altered mRNA levels of over 45 genes involved in neurotransmission, especially those regulating GABA receptor subunits, dopamine and serotonin receptors, and ion channels within 1–3 hours of intranasal administration.

A strong correlation was observed between gene expression changes induced by Selank and GABA (r = 0.86, p ≤ 0.05), supporting GABAergic pathway involvement [1].

Modulation of Enkephalin-Degrading Enzymes and Neurotransmitter Balance

Selank’s therapeutic potential may stem in part from its ability to preserve and enhance endogenous neuropeptide activity. By inhibiting enzymes that degrade enkephalins (natural opioid peptides), Selank may strengthen the brain’s own pain-regulating and stress-buffering systems.

Combined with its influence on serotonin, dopamine, and BDNF levels, this points to a multifaceted role in stabilizing mood and neurochemical balance.

In a 2001 rodent study, Selank was shown to dose-dependently inhibit plasma enkephalinase activity in BALB/c mice—markedly increasing the half-life of endogenous leu‑enkephalin (IC₅₀ ≈ 15 µM). This pharmacological action correlated with observable anxiolytic effects in behavioral assays and outperformed standard peptidase inhibitors like bacitracin and puromycin [2].

Immunomodulatory and Cytokine Effects

Selank’s also plays a role in immune regulation. Preclinical studies indicate that Selank can modulate cytokine expression, particularly by balancing pro- and anti-inflammatory signals such as interleukin-6 (IL-6) and influencing Th1/Th2 immune responses. This immunomodulatory effect extends to both the central nervous system and the peripheral immune system.

By helping to maintain immune homeostasis, Selank may reduce neuroinflammation, a key factor in anxiety, cognitive decline, and mood disorders. Its dual action on neural and immune pathways suggests a broader therapeutic profile, thus supporting both psychological resilience and neuroprotection in stress-related conditions [3].

Research Applications of Selank

Selank is a synthetic peptide with growing interest in neuroscience and immunology research. Initially developed for its anxiolytic effects, it is now being explored for broader applications including cognitive enhancement, immune modulation, and neuroprotection.

1. Anxiety & Stress Modulation

In rodent studies, Selank consistently reduced anxiety-like behaviors in tests such as the elevated plus maze and open field.

Notably, in a chronic mild stress model, Selank not only mimicked the effects of diazepam but also enhanced its efficacy when co-administered. Unlike benzodiazepines, however, Selank produced these calming effects without sedative side effects or impairing coordination, suggesting a safer anxiolytic profile [4].

In this regard, Selank’s mechanism appears linked to allosteric modulation of GABAA receptors, improving inhibitory neurotransmission.

2. Cognitive Enhancement & Memory Support

Animal studies have found that Selank supports learning and memory, particularly under stress. In food-reward conditioning tasks, Selank-treated rats exhibited faster memory consolidation and retention, likely via increased BDNF expression and elevated serotonin and dopamine activity.

Selank‑treated rats exhibited faster memory consolidation, fewer errors, and improved retention, especially in subjects with initially poor learning ability [5].

3. Neuroprotective & Neurotrophic Effects

Selank’s neuroprotective potential is closely linked to its ability to promote neuroplasticity and support neuronal survival.

In rodent studies, intranasal administration of Selank led to a significant increase in brain-derived neurotrophic factor (BDNF) levels in the hippocampus within 24 hours—a region critical for memory and learning. BDNF plays a key role in synaptic plasticity, neuron growth, and cognitive resilience, especially under stress or injury.

Additionally, Selank has shown protective effects in animal models of oxidative stress, glutamate-induced excitotoxicity, and cerebral ischemia. These findings suggest that Selank may help stabilize neuronal environments, reduce inflammation, and limit cell death [1][4].

This highlights Selank’s potential as a therapeutic candidate in research related to stroke, traumatic brain injury, and neurodegenerative conditions (such as Alzheimer’s and Parkinson’s disease).

4. Immunomodulatory & Cytokine Regulation

Selank’s impact on the immune system extends beyond stress regulation, showing potential for broader immunological and anti-inflammatory applications.

In both preclinical and early clinical studies, including those involving patients with generalized anxiety disorder (GAD), Selank modulated key immune markers. It notably reduced levels of pro-inflammatory cytokine IL‑6, a molecule often elevated in chronic stress and inflammatory states.

At the same time, Selank helped normalize the Th1/Th2 cytokine balance, which is crucial for maintaining healthy immune responses without tipping toward autoimmunity or immune suppression [3][4].

These effects may be partly attributed to Selank’s structural similarity to tuftsin, a natural immunomodulatory peptide that enhances phagocytic activity and immune vigilance. Unlike many conventional immunosuppressants, Selank appears to promote immune resilience, supporting proper immune function under stress rather than broadly dampening it.

Selank Peptide Characteristics

• • Molecular Formula: C₃₃H₅₇N₁₁O₉
  • CAS Number: 129954‑34‑3
  • Amino Acid Sequence: H‑Thr‑Lys‑Pro‑Arg‑Pro‑Gly‑Pro‑OH (TKPRPGP)
  • Synonyms: Selanc, TP‑7, L‑threonyl‑L‑lysyl‑L‑prolyl‑L‑arginyl‑L‑prolylglycyl‑L‑proline
  • Molar Mass: ~751.9 Da
  • Appearance: White to off-white lyophilized powder
  • Solubility: • ≥100 µg/mL in sterile water; ~10 mg/mL in PBS (pH 7.2)

• Storage Recommendations (Lyophilized powder)

• • • Short-term (weeks): room temperature or 39.2°F (4 °C)
    • Long-term (months–years): 68°F (–20 °C) (2 years), -112°F (–80 °C) (optimal)

• Storage Recommendations (Reconstituted solution)

• • In PBS or sterile water: store 2–7 days at 39°F (4 °C); freeze at -4°F/-112°F (–20 °C/–80 °C) for long-term (up to 6 months); minimize freeze-thaw cycles

Selank is commonly supplied as acetate salt; theoretical formula C₃₃H₅₇N₁₁O₉•C₂H₄O₂; molar mass ~811.9 Da.

Selank vs Semax vs PRL‑8‑53 Comparison

Feature	Selank	Semax	PRL‑8‑53
Type	Synthetic heptapeptide (Thr‑Lys‑Pro‑Arg‑Pro‑Gly‑Pro)	Synthetic heptapeptide (Met‑Glu‑His‑Phe‑Pro‑Gly‑Pro)	Synthetic phenethylamine nootropic
CAS Number	129954‑34‑3	80714‑61‑0	51352‑88‑6
Molecular Formula	C₃₃H₅₇N₁₁O₉	C₃₇H₅₁N₉O₁₀S	C₁₈H₂₁NO₂
Molar Mass	~751.9 g/mol	~813.9 g/mol	n/a – small molecule, ~299 g/mol
Primary Targets	Anxiolytic pathways, GABAergic, immune modulation	Neuroprotection, BDNF/TrkB, neuroplasticity	Cognitive enhancement, memory encoding
Mechanism Complexity	Moderate – GABAergic, cytokine, neurotransmitter modulation	Moderate – neurotrophic, melanocortin interaction, enkephalinase inhibition	Simple – cholinergic and dopaminergic modulation
Research Focus Areas	Anxiety, mood, stress resilience, immunity	Stroke, cognitive decline, memory, neuroprotection	Learning and memory enhancement
Administration Route	Intranasal, subcutaneous, IV	Intranasal	Oral or sublingual (preclinical/human studies)
Stability & Storage	Stable as lyophilized powder, refrigerated; avoid heat (>70 °C)	Stable under proper storage; refrigerated, lyophilized form	Stable small molecule; typical ambient conditions
Approval Status	Research use only; not approved	Approved in Russia; research elsewhere	Research only; not approved for any use
Disclaimer	Research reagent only — not for human/veterinary use	Research reagent only — except sanctioned use in Russia	Research reagent only — not approved

Selank Safety and Side Effects in Studies

Research on Selank is primarily preclinical or conducted in early human observations. At standard research doses, no significant adverse effects have been documented.

A 2017 study investigated Selank (along with other peptides) on mouse embryonic stem cells and found no signs of toxicity at concentrations up to 100 µM — cell survival and differentiation remained normal [6].

In rat models of Parkinson’s disease (6-OHDA lesions), Selank did not impair motor performance and showed anxiolytic effects without sedation or motor dysfunction [7]. Rats receiving Selank alongside diazepam under stress exhibited enhanced anxiolytic effects with no observed sedation or cognitive impairment [1].

However, human safety data remain limited, and no claims can be made about safety in humans.

Legal Disclaimer

This product is intended strictly for laboratory research purposes and is not approved for human or veterinary use. It is supplied exclusively for qualified researchers and institutions involved in scientific investigation.

Selank is not intended for ingestion, injection, or application to humans or animals, and should never be used in any form of self-experimentation. Any mention of biological effects or mechanisms of action is provided solely for informational and scientific discussion and does not imply suitability for therapeutic, diagnostic, or medical use.

By purchasing this compound, the buyer agrees to use it in accordance with all applicable laws, regulations, and research safety protocols.

Certificate of Analysis (COA)

Every batch of Selank (and all peptides) from Evolve Peptides is linked to a batch-specific Certificate of Analysis, conducted by independent third-party laboratories. This rigorous testing verifies:

• Peptide identity
• Sterility and microbial testing
• Endotoxin levels (where applicable)

COAs are available for every vial per batch, ensuring full transparency and research-grade confidence.

If you prefer to conduct your own independent verification, we’ll even replace the product used in your third-party test—just provide your lab results along with your order number.

Scientific References

1. Volkova, A., Shadrina, M., Kolomin, T., Andreeva, L., Limborska, S., Myasoedov, N., & Slominsky, P. (2016).
   Selank administration affects the expression of some genes involved in GABAergic neurotransmission.
   Frontiers in Pharmacology, 7, Article 31.
   https://europepmc.org/article/PMC/PMC4757669
   
2. Zozulya, A. A., Kost, N. V., Sokolov, O. Y., et al. (2001).
   The inhibitory effect of Selank on enkephalin-degrading enzymes as a possible mechanism of its anxiolytic activity.
   Bulletin of Experimental Biology and Medicine, 131, 315–317.
   https://link.springer.com/article/10.1023/A:1017979514274
   
3. Kolomin, T., Shadrina, M., Andreeva, L., Slominsky, P., Limborska, S., & Myasoedov, N. (2011).
   Expression of inflammation-related genes in mouse spleen under tuftsin analog Selank.
   Regulatory Peptides, 170(1–3), 18–23.
   https://www.sciencedirect.com/science/article/abs/pii/S0167011511000863
   
4. Kasian, A., Kolomin, T., Andreeva, L., Bondarenko, E., Myasoedov, N., Slominsky, P., & Shadrina, M. (2017).
   Peptide Selank enhances the effect of diazepam in reducing anxiety in unpredictable chronic mild stress conditions in rats.
   Behavioural Neurology, 2017, 5091027.
   https://pmc.ncbi.nlm.nih.gov/articles/PMC5322660/
   
5. Kozlovskii, I. I., & Danchev, N. D. (2003).
   The optimizing action of the synthetic peptide Selank on a conditioned active avoidance reflex in rats.
   Neuroscience and Behavioral Physiology, 33(7), 639–643.
   https://link.springer.com/article/10.1023/A:1024444321191
   
6. Storozhevykh, T. P., Tukhbatova, G. R., Senilova, Y. E., Pinelis, V. G., & Andreeva, L. A. (2017).
   Studying the toxic effects of some biologically active peptides on mouse embryonic stem cells.
   Bulletin of Experimental Biology and Medicine, 163(1), 24–28.
   https://pubmed.ncbi.nlm.nih.gov/29063333/
   
7. Slominsky, P. A., Shadrina, M. I., Kolomin, T. A., Stavrovskaya, A. V., Filatova, E. V., Andreeva, L. A., Illarioshkin, S. N., & Myasoedov, N. F. (2017).
   Peptides Semax and Selank affect the behavior of rats with 6-OHDA–induced PD-like parkinsonism.
   Doklady Biological Sciences, 474(1), 106–109.
   https://link.springer.com/article/10.1134/S0012496617030048