Selank — Anxiolytic & Immunomodulatory Research Heptapeptide | Klene Peptides

For Research Use Only | Not for Human or Veterinary Administration

Selank is a synthetic heptapeptide developed at the Institute of Molecular Genetics of the Russian Academy of Sciences as a stable, bioactive analog of the endogenous immunopeptide tuftsin (Thr-Lys-Pro-Arg). By extending the tuftsin tetrapeptide core with a C-terminal Gly-Pro-Pro addition to increase enzymatic stability, Selank achieves a substantially longer functional duration than native tuftsin while retaining and expanding its immune and CNS regulatory activity. Selank has demonstrated anxiolytic, nootropic, and immunomodulatory effects through GABAergic modulation, serotonin transporter upregulation, enkephalinase inhibition, and BDNF elevation — without the sedation, dependence, or cognitive impairment associated with benzodiazepine-class compounds. It is registered as a pharmaceutical in Russia for treatment of anxiety disorders and as a nootropic agent. Klene Peptides supplies Selank to USA research institutions with verified purity and same-day fulfillment.

Every vial from Klene Peptides includes:

Chemical Identity & Structural Profile

Parameter	Value
Full Name	Selank
Sequence	Thr-Lys-Pro-Arg-Pro-Gly-Pro
Parent Structure	Tuftsin (Thr-Lys-Pro-Arg) + Gly-Pro-Pro stabilizing C-terminal extension
Molecular Formula	C₃₃H₅₇N₁₁O₉
Molecular Weight	~751.9 g/mol
CAS Number	129954-34-3
Origin	Institute of Molecular Genetics, Russian Academy of Sciences
Registration	Approved pharmaceutical in Russia (anxiolytic / nootropic)
Appearance	White lyophilized powder
Solubility	Water, 0.9% saline
Storage	Lyophilized: −20°C; Reconstituted: 4°C, use within 14 days
Common Research Delivery	Intranasal (0.15% solution), SC, IP

Mechanism of Action

GABAergic & Neurochemical Mechanisms

Mechanism	Effect	Research Significance
GABA-A positive allosteric modulation	Benzodiazepine-like anxiolytic without direct BZD receptor binding	Anxiety reduction without dependence or tolerance
Serotonin transporter (SERT) upregulation	Increased serotonergic tone	Mood and affective regulation studies
Enkephalinase inhibition	Elevated endogenous met-enkephalin levels	Endogenous opioid peptide system interaction
Dopamine system modulation	Dopaminergic tone normalization	Motivation, reward, and cognitive function research
BDNF upregulation	Neuroplasticity and neurogenesis support	Cognitive enhancement and neuroprotection
NGF modulation	Neurotrophic factor elevation	Synaptic plasticity and cholinergic research

Immunomodulatory Mechanisms (Tuftsin Core)

Mechanism	Cell Target	Effect
IL-6 normalization	Monocytes, macrophages	Anti-inflammatory immune tone regulation
IFN-γ modulation	T cells	Th1/Th2 cytokine balance research
NK cell activity	Natural killer cells	Innate immune surveillance studies
Phagocytic stimulation	Macrophages, neutrophils	Immune function enhancement models
Leukocyte migration	Myeloid cell populations	Immune trafficking research

Pharmacokinetic & ADME Profile

Parameter	Value	Notes
Molecular Weight	~751.9 g/mol	CNS penetration confirmed
BBB Penetration	Demonstrated	Confirmed CNS activity in pharmacological studies
Routes (Research)	SC, IP, intranasal	Intranasal is the primary clinical delivery route
Plasma Half-Life	~2–5 minutes (blood)	Short; CNS functional effects persist 10–20+ hours
Bioavailability (intranasal)	Moderate to good	Olfactory nerve pathway enables direct CNS delivery
Metabolism	Aminopeptidase and endopeptidase cleavage	Pro-Pro extension confers greater stability vs. native tuftsin
Excretion	Renal	Metabolite clearance

Research note: Selank’s short plasma half-life paradoxically produces neurological effects lasting many hours, attributed to BDNF gene expression activation and receptor-independent transcriptional mechanisms. This PK/PD dissociation is a key area of mechanistic investigation.

Research Applications

Anxiety & Stress Response Models

Model	Research Outcome
Elevated plus maze (EPM)	Significant anxiolytic effect without sedation
Open field test	Reduced anxiety behavior; locomotion maintained
Conditioned emotional response	Anxiety extinction facilitation
Social stress models	HPA axis normalization; corticosterone reduction
Generalized anxiety disorder (Russian clinical trials)	Comparable efficacy to benzodiazepines without dependence

Cognitive & Nootropic Research

Parameter	Effect
Memory consolidation	Improved in passive avoidance and spatial memory tasks
Attention and processing speed	Enhancement observed in clinical cognitive assessments
BDNF elevation	Dose-dependent; sustained over 24 hours
Learning (Morris water maze)	Improved spatial learning parameters

Immunological Research

Selank’s tuftsin-derived core retains immunostimulatory properties relevant to:

Depression & Neuropsychiatric Research

Research Dosing Reference

For scientific reference only — not prescriptive recommendations

Research Model	Reported Dose Range	Route	Duration
Anxiety models (rodent)	100–400 mcg/kg	SC, IP	Acute or 5–14 days
Cognitive function	100–300 mcg/kg	SC, IP	5–14 days
Immunomodulation	100–300 mcg/kg	SC	7–21 days
In vitro (cell assays)	0.1–10 µM	Cell culture	Per experiment
Clinical reference (intranasal)	400 mcg (flat dose)	Intranasal	Daily per trial design

Ranges derived from Russian pharmacological literature and PMC-indexed research.

Reconstitution Reference

Lyophilized Amount	Sterile/Bacteriostatic Water	Concentration
5 mg	2.5 mL	2.0 mg/mL
10 mg	5.0 mL	2.0 mg/mL

Klene Peptides Quality Standards

Certificate of Analysis — Standard Parameters

Every batch supplied by Klene Peptides is verified against the following analytical benchmarks:

Test	Specification	Method
Purity	≥99%	HPLC (High-Performance Liquid Chromatography)
Molecular Identification	Confirmed	HPLC-MS (High-Performance Liquid Chromatography – Mass Spectrometry)
Water Content	<1.5%	—

What Every Klene Peptides Order Includes

Ordering Selank for Your Research Program

Important Research Compliance Notice

All products sold by Klene Peptides are strictly for in vitro research and laboratory investigation purposes only. Selank supplied by KlenePeptides.net has not been evaluated by the FDA for human safety or efficacy. It is not approved for human or veterinary administration in the United States. Purchase, possession, and use must comply with all applicable federal, state, and local regulations. This content is intended for licensed researchers and qualified scientific personnel only.

Scientific References

Zozulia AA, et al. "Efficacy and possible mechanisms of action of a new peptide anxiolytic Selank in the therapy of generalized anxiety disorder and neurasthenia." Zh Nevrol Psikhiatr Im S S Korsakova. 2008;108(4):38-48.
Semenova TP, et al. "Effects of Selank on the development of anxiety and conditioned fear reactions in rats." Eksp Klin Farmakol. 2010;73(8):2-5.
Uchakina ON, et al. "Immunomodulatory effects of Selank in patients with anxiety-asthenic disorders." Zh Nevrol Psikhiatr Im S S Korsakova. 2008.
Ashmarin IP, et al. "The functional continuum of neuroactive peptides: the case of tuftsin and its analog Selank." Neurochem J. 2007.
Malkova NV, et al. "Effects of Selank on mRNA expression in the rat brain." Bull Exp Biol Med. 2012.
Golubeva AV, et al. "BDNF and serotonin transporter changes with Selank treatment." Russian Pharmacological Journal. 2011.
PubChem. Selank. CID: 11979755. https://pubchem.ncbi.nlm.nih.gov