Heptapeptide is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-03-02. Numbers and descriptions here follow the published literature rather than marketing material.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed as a stabilized analogue of tuftsin, a naturally occurring tetrapeptide fragment derived from the immunoglobulin heavy chain. The additional Pro-Gly-Pro segment at the carboxyl terminus is intended to slow enzymatic cleavage. The compound is usually described in the literature as a synthetic peptide with anxiolytic and cognitive-related activity, a label that reflects a research context rather than an approved therapeutic category.
Most published work on selank originates from a small number of research groups in the Russian Federation. A large share of that record appears in Russian-language journals, which limits access for readers who rely on English-indexed databases. Independent replication by laboratories outside the original research network is sparse in publicly available sources. This concentration of origin and language is a frequently noted feature when the compound is summarized in broader reviews of synthetic peptides.
Laboratory work relies on standard behavioral paradigms. Rodents are tested in the elevated plus maze, open field, and passive avoidance tasks, with outcomes compared against diazepam or vehicle controls. Intranasal dosing is used most often because it bypasses first-pass metabolism, though intraperitoneal and intravenous routes also appear in published protocols. Biochemical endpoints include tissue BDNF concentrations, cytokine levels, and monoamine metabolites. Human data are limited to small Russian trials reporting reduced anxiety scores; most were not prospectively registered, and few employed independent outcome assessment.
Measuring peptide exposure inside the brain is technically difficult. Selank is degraded rapidly in plasma, and assays must separate intact peptide from fragments, which favors targeted mass spectrometry over immunoassays alone. Reported half-lives are short, on the order of minutes, so effects observed hours later are attributed to downstream signaling rather than to the parent compound. Blood-brain barrier permeability is debated and rarely quantified directly. Gaps include absent dose-response characterization, inconsistent reporting of purity, and almost no pharmacokinetic data from human participants.
Selank is studied chiefly as an animal-model anxiolytic with proposed secondary effects on memory and immune signaling. Reported mechanisms include modulation of the GABA-A receptor complex, inhibition of enkephalin-degrading enzymes, and shifts in monoamine turnover within limbic structures. Some experiments describe increased expression of brain-derived neurotrophic factor in the hippocampus after repeated dosing. No single molecular target has been confirmed, and the peptide does not bind any receptor with the selectivity typical of a conventional small-molecule drug. Mechanism therefore remains a set of hypotheses rather than an established pathway.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C33H57N11O9 | Derived from the seven-residue sequence |
| Molecular weight | About 751.9 g/mol | Average mass; the monoisotopic value is slightly lower |
| Residue count | Seven amino acids | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Parent compound | Tuftsin (Thr-Lys-Pro-Arg) | Selank extends tuftsin at the C-terminus |
| Compound class | Synthetic short peptide | Studied in a research setting; not a licensed drug in most markets |
Naming for this compound is not fully standardised in English sources. The spelling Selanc appears in some transliterations, and catalogue entries may instead list the peptide sequence itself as the identifier. Reference material sometimes groups it with other short synthetic peptides studied for behavioural effects, which can create confusion when citations are compared. Distinguishing the exact sequence from related tuftsin analogues is therefore a practical first step when reviewing any dataset or specification sheet.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, frequently abbreviated as TKPRPGP. It was designed as a structural analogue of tuftsin, a naturally occurring tetrapeptide released by enzymatic cleavage of the immunoglobulin heavy chain. The two additional proline residues at the C-terminal end extend the parent chain and change how the molecule behaves in solution. The free peptide has a calculated molecular mass of approximately 751.9 g/mol and is generally supplied as a lyophilised white to off-white powder.
Development work on the compound began in the 1980s and 1990s at the Institute of Molecular Genetics in Moscow, within the same research programme that produced the peptide Semax. Early investigators sought a tuftsin derivative with improved resistance to enzymatic breakdown and with activity in the central nervous system after peripheral administration. Most of the primary literature from this period was published in Russian, a factor that still shapes how easily the findings can be checked by outside groups.
Published clinical evidence is limited. Most controlled trials were conducted in Russia, enrolled modest numbers of participants, and appeared in Russian-language journals, which restricts independent verification. Reported outcomes include lower anxiety scores, improved attention and memory measures, and changes in fatigue ratings. Reviews written in English note methodological limitations such as small samples and inconsistent endpoints. Whether the compound produces clinically meaningful benefit relative to established anxiolytics is therefore an open question rather than an established finding.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences as a structural analogue of tuftsin, a naturally occurring tetrapeptide fragment of the immunoglobulin heavy chain. The added Pro-Gly-Pro tail was intended to slow enzymatic degradation and extend biological activity. In Russia it is registered as an anxiolytic nasal preparation, while regulators elsewhere have not approved it for clinical use.
Reversed-phase high-performance liquid chromatography is the standard technique for estimating peptide purity. The result is a peak-area percentage, which describes how much of the detected material elutes as the main peak in one run. Mass spectrometry confirms the molecular mass and can reveal truncated, adducted, or otherwise modified species. Amino acid analysis or tandem mass spectrometry can address sequence fidelity when identity is in doubt. None of these measurements, taken alone, establishes that a sample is fit for any specific purpose.
Lyophilized selank is normally supplied as a dry powder and is considered stable for extended periods when kept cold and dry. Moisture uptake is the main practical threat, because absorbed water promotes both hydrolysis and aggregation in the solid state. Vials are usually warmed to room temperature before opening so that condensation does not form on the powder. Supplier documentation commonly specifies -20 °C for routine storage, with -80 °C used for material intended to be archived for years.
Once dissolved, the peptide is markedly less stable than the dry powder. Aqueous solutions are subject to backbone hydrolysis and to microbial growth when they are handled without sterile technique. Buffered solutions near neutral pH are common for short-term laboratory work, while acidic conditions are sometimes used to improve solubility. Analytical laboratories generally prepare working solutions fresh rather than storing them, and a residual water film left in a reopened vial can seed degradation even when the container appears dry.
Lyophilized material is generally stable for extended periods when kept dry at or below minus twenty degrees Celsius. Working solutions are less stable, and common practice is to aliquot and freeze them so that repeated freeze-thaw cycles are avoided. Aqueous solutions are sensitive to pH extremes and to microbial growth, so short-term storage at refrigerator temperature is typical. Oxidation and hydrolysis are the principal degradation routes. Reconstitution with sterile water or a mild buffer is standard, and solutions should be protected from light.
Regulatory treatment varies by jurisdiction. In Russia the compound is a registered prescription product, while in the European Union and the United States it is generally handled as a research chemical without a marketing authorization. Suppliers therefore operate outside pharmaceutical oversight, and buyers rely on supplier documentation for purity and identity claims. Chain of custody and third-party testing are the main verification tools. Analysts note that the absence of a pharmacopoeial monograph for research-grade material limits standardization across vendors.
Purity assessment relies mainly on reverse-phase high-performance liquid chromatography with ultraviolet detection. Because the peptide lacks a strong chromophore, detection often uses backbone absorbance near 214 nm. Identity is confirmed by mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, comparing the measured mass against the expected value. Amino acid analysis can verify composition after acid hydrolysis. Diastereomer content and residual counterions are reported less often, although both can influence biological assays.
=== Copolymer engineering === Copolymerization is used to modify the properties of manufactured plastics to meet specific needs, for example to reduce crystallinity, modify glass transition temperature, control wetting properties or to improve solubility. It is a way of improving mechanical properties, in a technique known as rubber toughening. Elastomeric phases within a rigid matrix act as crack arrestors, and so increase the energy absorption when the material is impacted for example. Acrylonitrile butadiene styrene is a common example.
== Research == Gene therapy is currently being studied as a possible treatment for chronic granulomatous disease. CGD is well-suited for gene therapy since it is caused by a mutation in single gene which only affects one body system (the hematopoietic system). Viruses have been used to deliver a normal gp91 gene to rats with a mutation in this gene, and subsequently the phagocytes in these rats were able to produce oxygen radicals. In 2006, two human patients with X-linked chronic granulomatous disease underwent gene therapy and blood cell precursor stem cell transplantation to their bone marrow. Both patients recovered from their CGD, clearing pre-existing infections and demonstrating increased oxidase activity in their neutrophils. However, long-term complications and efficacy of this therapy were unknown. In 2012, a 16-year-old boy with CGD was treated at the Great Ormond Street Hospital, London with an experimental gene therapy that temporarily reversed the CGD and allowed him to overcome a life-threatening lung disease. In 2024, Prime Medicine began a Phase 1/2 open-label clinical trial to evaluate PM359, an investigational gene therapy, in patients with CGD caused by NCF1 mutations. The treatment involves transplantation of autologous CD34+ stem cells modified by prime editing ex vivo. Following an announcement of preliminary results in May 2025, Prime Medicine and its clinical collaborators reported in December 2025 that two CGD patients treated with PM359 had been "effectively cured" of the disease.
==== March 2024 ==== On 4 March, a Hezbollah anti-tank missile strike on Margaliot resulted in seven injuries as well as the death of an Indian national. The next day, an Israeli airstrike on Hula, in retaliation for the previous day's strike on Margaliot, killed three Lebanese citizens, a married couple and their child. Amongst the three killed, Hezbollah announced two as their members. On 9 March, five people, including three Hezbollah members, were killed and at least nine others were wounded in an IDF strike on a house in Khirbet Selm. In retaliation, the next day Hezbollah fired 37 Katyusha rockets at the Mount Meron in northern Israel; no injuries were reported.
Feoktist I. Bogoyavlenskiy (1933–1935) Vasiliy V. Evlampiev (1935–1939) Faizi F. Faizyllin (1958–1960) Boris A. Arbuzov (1941–1950) Arkadiy N. Pudovik (1950–1958) Faizi F. Faizyllin (1958–1960) Vera F. Toropova (1960–1965) Alexander I. Kostromin (1965–1968) Alexander I. Konovalov (1968–1972) Irina V. Konovalova (1972–1987) Galina A. Chmutova (1987–1992) Nikolai A. Ulakhovich (1992–2000) Vladimir I. Galkin (since 2000– until present) Department of Analytical Chemistry Department of High Molecular and Organoelement Compounds Department of Inorganic Chemistry Department of Organic Chemistry Department of Physical Chemistry Department of Chemical Education Department of Environmental Chemistry Department of Applied Chemistry Department of Stereochemistry Division for Analytical Chemistry Division for Inorganic Chemistry and Coordination chemistry Division for Organic Chemistry Division for Physical Chemistry Division for Organoelement Compounds Division for Stereochemistry Division for Applied Chemistry Division for Environmental Chemistry
Sources: en.wikipedia.org
=== Marketing authorization === In 2011, the European Medicines Agency (EMA) granted a marketing authorisation for a buccal application form of midazolam, sold under the brand name Buccolam. Buccolam was initially approved for the treatment of prolonged, acute, convulsive seizures in people from three months to less than 18 years of age. This is the first application of a paediatric-use marketing authorisation by the EMA.
== First Ministry == On 16 February 1993, the Governor, Sir Francis Burt, designated 17 principal executive offices of the Government under section 43(2) of the Constitution Acts Amendment Act 1899. The following ministers were then appointed to the positions, and served until the reconstitution of the Ministry on 10 February 1995. The list below is ordered by decreasing seniority within the Cabinet, as indicated by the Government Gazette and the Hansard index. Blue entries indicate members of the Liberal Party, whilst green entries indicate members of the National Party.
It also has the largest Brazilian community in the UK; one of the largest Indian communities; a significant Afro-Caribbean community; and more recent Romanian, Polish and Somali communities. The 2021 census showed that 1.3% of adults in Brent identified as transgender, derived from the Census question, "Is the gender you identify with the same as your sex registered at birth?". This gave Brent the second highest proportion of transgender adults after the Borough of Newham (at 1.5%). The overall proportion in England and Wales was 0.5% with Brighton, an area well known for its LGBT communities, 1%. However, Prof Michael Biggs of Oxford University showed there was a correlation between the proportion of transgender people in these areas and the proportion for whom English was not their first language (34% in Brent and 35% in Newham, compared to 9% nationally), suggesting the question was not fully understood by some. Prof Biggs described the figures as "irredeemably flawed". In September 2024, Mary Gregory, a deputy director at the ONS said some people may have misunderstood the question, saying there was "potential bias" in how the question was answered "by those who responded that they had lower levels of English proficiency, some of whom may have mistakenly given an answer suggesting they were trans". As a result, the ONS downgraded the data from "accredited official statistics" to "official statistics in development" to reflect the possible flaws.
class I "fish-like" – hydrophilic odorants class II "tetrapod-specific" – more hydrophobic compounds In the current scheme, class I corresponds to alpha and beta while class II corresponds to gamma. Gamma is not actually tetrapod specific: it's just present in many more copies in tetrapods.
In 1547, Ivan the Terrible was crowned in Moscow as not only the grand prince, but also the first tsar of all Russia. During the 16th and 17th centuries, three circular defenses were built around the town: Kitay-gorod, the White City, and the Earthen City. However, in 1547, fires destroyed much of the town, and in 1571 the Crimean Tatars captured Moscow, burning everything except the Kremlin. The annals record that only 30,000 of 200,000 inhabitants survived. The Crimean Tatars attacked again in 1591, but they were held back by new defensive walls, built between 1584 and 1591 by a craftsman named Fyodor Kon. In 1592, an outer earth rampart with 50 towers was erected around the city, including an area on the right bank of the Moscow River. As an outermost line of defense, a chain of strongly fortified monasteries was established beyond the ramparts to the south and east—principally the Novodevichy Convent and the Donskoy, Danilov, Simonov, Novospasskiy, and Andronikov monasteries, most of which now house museums. Because of its ramparts, the city became known poetically as Bielokamennaya, the "White-Walled". The city limits, as marked by those ramparts, are marked by the Garden Ring in contemporary Moscow. Three square gates existed on the east side of the Kremlin wall, which in the 17th century were known as Konstantino-Eleninsky, Spassky, and Nikolsky (after the icons of Constantine and Helen, the Savior, and St. Nicholas that hung over those gates).
Sources: en.wikipedia.org
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, designed as a metabolically stabilized analogue of the endogenous tetrapeptide tuftsin. It has been studied mainly against anxiety-related and cognitive endpoints rather than as an approved medicine in most jurisdictions.
Tuftsin contains four residues, while selank carries an additional Pro-Gly-Pro segment at the carboxyl end. That extension is intended to reduce enzymatic cleavage. Comparative pharmacokinetic data in humans remain limited.
No single receptor target is widely accepted as the definitive mediator of the reported effects. Proposed contributors include GABAergic modulation, shifts in monoamine turnover, and altered neuropeptide degradation. The mechanism is treated in the literature as unresolved.
Intranasal administration predominates in both animal and human research because it avoids hepatic first-pass metabolism. Injectable and intraperitoneal routes appear in animal work mainly for comparison.