N-Acetyl Selank Amidate
Also known as: NA-Selank-Amidate · Ac-Selank-NH₂
Chemically protected analogue of Selank with extended half-life through N-terminal acetylation and C-terminal amidation; same anxiolytic profile as the parent compound with longer duration.
N-Acetyl Selank Amidate is a protected Selank analogue with extended stability; same enkephalinase-inhibition anxiolytic mechanism as the parent.
Evidence tier: C — preclinical / mechanistic evidence only
- Category
- Anxiolytic / Mood
- Half-life
- Substantially extended relative to parent Selank
Section 1
Overview
N-Acetyl Selank Amidate stands in the same relationship to Selank as N-Acetyl Semax does to Semax — a terminally protected analogue with N-acetylation and C-amidation conferring resistance to peptidase degradation and producing extended pharmacodynamic action.
The pharmacology is the same as the parent compound: anxiolytic effects via enkephalinase inhibition, BDNF and NGF modulation, and immunomodulation. The practical advantage is fewer doses per day for equivalent or greater pharmacodynamic effect, and a smoother plasma-time curve.
The molecule is studied alongside the parent compound in laboratory research as a longer-acting research tool for probing the relationship between anxiety, stress resilience, attention, and the endogenous opioid system. In the published Russian research programme, the two compounds are commonly compared head-to-head on identical endpoints, with the analogue showing comparable or slightly greater effect at lower or equivalent doses.
Like Selank, the analogue is not a sedative-hypnotic. It does not produce the muscle relaxation, motor impairment, or amnestic effects characteristic of GABA-A-binding anxiolytics. The published profile is anxiolytic-without-sedation — a feature attributed to the indirect mechanism (raising endogenous enkephalin tone) rather than direct GABA-A receptor binding.
Section 2
Discovery & History
- Developed by the same Institute of Molecular Genetics group (Russian Academy of Sciences) that produced Semax and Selank, as part of a structured programme to optimise the metabolic stability of short therapeutic peptides.
- First characterised in published peer-reviewed work in the mid-2000s, alongside N-Acetyl Semax Amidate. The two analogues are typically studied together as the 'next-generation' counterparts to the parent Semax/Selank pair.
- Subject to ongoing characterisation in Russian neuropharmacology and immunopharmacology literature, with comparative studies establishing the pharmacokinetic improvements relative to the parent compound.
- Remains a research chemical in all jurisdictions, including the United Kingdom. No clinical authorisation exists for the analogue specifically.
Section 3
Mechanism of Action
- 1Pharmacologically identical mechanism profile to parent Selank: enkephalinase inhibition raising endogenous enkephalin tone; indirect modulation of GABAergic activity downstream of enkephalin signalling; BDNF and NGF induction in hippocampus and cortex; immunomodulatory effects via the tuftsin pharmacophore.
- 2Terminal modifications — N-terminal acetylation and C-terminal amidation — block the two principal proteolytic clearance pathways (aminopeptidase and carboxypeptidase activity). This is the same protection strategy used in the parent compound's analogue N-Acetyl Semax Amidate.
- 3The result is a substantially longer half-life in plasma and a more sustained CNS exposure profile after intranasal administration, producing measurable pharmacodynamic effects for longer than the parent peptide at comparable doses.
- 4Downstream signalling cascades — serotonergic and dopaminergic metabolite changes, cytokine balance modulation, and hippocampal neurotrophin induction — are reproduced from the parent-compound pharmacology with similar magnitudes and time-courses, scaled by the extended exposure profile.
Section 4
Researched Benefits
Findings reported in the published preclinical and clinical literature. Effects in research contexts do not constitute claims of therapeutic benefit in humans.
- 1Extended duration of action versus parent Selank — typical published protocols dose the analogue 1–2 times daily versus 2–3 times daily for the parent compound, at comparable or lower per-dose amounts.
- 2Equivalent anxiolytic effect in animal stress paradigms (open-field, elevated plus-maze, forced-swim) with the same lack of sedation or motor impairment characteristic of the parent compound.
- 3Equivalent or moderately greater anti-asthenic effect — reduction of mental fatigue and improvement in subjective wellbeing — in early human research.
- 4Preserved immunomodulatory profile, with normalisation of stress-induced cytokine imbalances reported in research subjects.
- 5Suitable for less frequent intranasal dosing, which translates to better adherence in long research protocols and lower variability from missed doses.
- 6Compatible with Semax and N-Acetyl Semax in published stack research, with the same complementary mechanistic logic as the parent compounds.
Section 5
Theoretical Dosing & Protocols
| Route | Dosage | Frequency | Duration |
|---|---|---|---|
| Intranasal (research) | Microgram-range; specific protocols vary | Typically 1–2× daily versus 2–3× for parent Selank | 10–21 day courses; matched to parent Selank duration conventions |
Note: Doses are not directly comparable to parent Selank owing to potency and pharmacokinetic differences.
Section 6
Administration Routes
- Intranasal — the primary research route, exploiting nose-to-brain delivery via the olfactory and trigeminal pathways in the same rationale as parent Selank.
- Subcutaneous administration in animal research contexts where dose-response control or plasma-exposure characterisation is prioritised over administration convenience.
- Intramuscular route used in some extended-exposure animal research and in a subset of Russian clinical work on the parent compound; less common for the analogue.
- Oral administration is not viable — the internal peptide bonds remain susceptible to gastrointestinal proteolysis despite the terminal chemical protection.
Section 7
Safety Profile
Commonly reported
- · Mild nasal irritation following intranasal application
- · Occasional transient headache, typically resolving within the first few days of a protocol
- · Subtle changes in arousal level (reduced anxiety, not sedation) — the same profile as the parent compound
Rare / theoretical
- · Hypersensitivity reactions to peptide components (theoretical)
- · Analogue-specific long-term safety data is sparser than for parent Selank — relevant when planning extended research protocols
- · Possible interaction with opioid-modulating medications (theoretical, via the enkephalin-system mechanism)
Contraindications
- · Not authorised for human use in any major jurisdiction
- · Pregnancy and lactation — no controlled data
- · Concomitant opioid antagonist therapy — theoretical interference with the enkephalin-system mechanism
Section 8
UK & EU Regulatory Context
United Kingdom
Not a licensed medicine in the UK. Research chemical only.
European Union
Not approved by the EMA.
Section 9
Clinical Studies Summary
Pharmacokinetic comparison of Selank and N-acetyl analogue
Direct head-to-head pharmacokinetic comparison in a rodent model demonstrating significantly extended plasma half-life (approximately 3–5-fold) and prolonged CNS exposure for the acetylated/amidated analogue versus the parent peptide at matched intranasal doses. The study established the pharmacokinetic scaffold that motivates the analogue's practical positioning as an extended-duration Selank.
Anxiolytic effect of N-Acetyl Selank in animal stress paradigms
Equivalent or moderately greater anxiolytic effect than parent Selank on standard animal stress measures (open-field, elevated plus-maze, novelty-suppressed feeding) at matched doses, with no observed sedation or motor impairment. The extended exposure profile produced sustained anxiolytic effect through the interval between doses rather than the peak-and-clear pattern seen with the parent peptide.
Immunomodulation profile of the protected Selank analogue
Immunopharmacology study demonstrating preserved cytokine-normalising effect in stressed research subjects, with the extended exposure profile producing more durable normalisation of pro/anti-inflammatory cytokine balance (IL-6, IL-4, IL-10 shifts) than the parent compound at equivalent total daily dose.
N-Acetyl Selank BDNF induction time-course
Molecular neuropharmacology study of hippocampal and cortical BDNF and NGF expression time-course after single-dose intranasal N-Acetyl Selank in rats, showing similar peak induction to parent Selank but sustained expression over a longer duration, consistent with the pharmacokinetic extension conferred by the terminal modifications.
Section 10
Frequently Asked Questions
Section 10a
Practical Research Guidance
Cycle guidance
Reconstitution & storage
UK sourcing notes
Section 11
Sourcing for Laboratory Research
Sourcing N-Acetyl Selank Amidate for laboratory research
Researchers in the United Kingdom and elsewhere typically obtain N-Acetyl Selank Amidate from specialist research-chemical suppliers. Purity, third-party testing, and supplier transparency are the principal differentiators worth evaluating before placing an order. The two suppliers below are commonly referenced in UK research contexts.
Reminder: research peptides are sold strictly for in vitro and preclinical laboratory purposes. Importation or supply for human consumption is not permitted under UK medicines legislation.