The short version of heptapeptide fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-07-30. Anything still debated is marked as such rather than presented as settled.
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.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. Its four N-terminal residues reproduce tuftsin, a tetrapeptide fragment of the immunoglobulin heavy chain, while the C-terminal Pro-Gly-Pro extension is a synthetic addition. The peptide has a molecular mass near 752 daltons and carries a net positive charge at physiological pH because of the arginine and lysine side chains. Published indexes list it under the name Selank and the sequence abbreviation TKPRPGP. Solid-phase peptide synthesis is the standard production route for research quantities.
Development took place at the Institute of Molecular Genetics of the Russian Academy of Sciences, where a series of short peptides were designed in the 1980s and 1990s. Selank was selected from variants of tuftsin that showed resistance to plasma peptidases. Russian regulatory approval covers it as an anxiolytic agent given intranasally. Outside that market the compound is normally handled as a research chemical rather than a medicine, and no widely recognised international pharmacopoeial monograph exists. The name Selank is a coined trade designation rather than a systematic chemical name.
| 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 |
Proposed mechanisms centre on modulation of the GABAergic system, with reports of altered expression of genes related to GABA-A receptor subunits and changed monoamine turnover. Some studies describe inhibition of enkephalinase, the enzyme that degrades endogenous enkephalins, which may prolong opioid peptide signalling. Effects on brain-derived neurotrophic factor and on cytokine expression have also been reported. These findings come largely from animal models and small human studies, and the precise primary target remains unresolved.
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.
Characterization of Selank in a laboratory setting relies on standard peptide methods. Reverse-phase high-performance liquid chromatography separates the target from related impurities and provides a purity figure, commonly reported as 95 percent or higher. Mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, confirms the molecular mass and helps detect truncation or modification. Amino acid analysis can verify composition when a sequence-level check is needed. These techniques together establish identity and purity for a given lot.
Lyophilized Selank, the dry powder form, is generally stored frozen at minus 20 degrees Celsius or colder for long-term keeping. The solid is hygroscopic and should stay sealed, dry, and protected from light. Once dissolved, the peptide is less stable and is usually held refrigerated at 2 to 8 degrees Celsius for short periods. Repeated freezing and thawing is avoided because it can promote aggregation and loss of activity. Buffers and pH choice also affect how long a solution remains usable.
Solubility behavior is a practical concern for handling. Selank dissolves readily in water and in common aqueous buffers, which simplifies preparation of working solutions. The choice of solvent, ionic strength, and pH can influence aggregation over time, particularly at higher concentrations. Aqueous solutions are typically sterile-filtered before use. Because stability depends on several variables, storage and handling notes should be treated as general guidance rather than fixed rules, and specific values are best confirmed against a certificate of analysis for each batch.
=== Frameworks === Artificial intelligence projects can be guided by ethical considerations during the design, development, and implementation of an AI system. An AI framework such as the Care and Act Framework, developed by the Alan Turing Institute and based on the SUM values, outlines four main ethical dimensions, defined as follows:
=== Cardiovascular system === Meta-analyses have reported a reduced risk of death from ischemic heart disease and from cerebrovascular disease among vegetarians. A 2023 systematic review and meta-analysis of prospective cohort studies found that vegetarian diets were associated with a reduced risk of cardiovascular disease overall and of ischemic heart disease in particular, while evidence for stroke was less clear.
== Dietary recommendations == Some research shows that most people in the United States and the United Kingdom consume sufficient vitamin B12. However, other research suggests that the proportion of people with low or marginal levels of vitamin B12 is up to 40% in the Western world. Grain-based foods can be fortified by having the vitamin added to them. Vitamin B12 supplements are available as single or multivitamin tablets. Pharmaceutical preparations of vitamin B12 may be given by intramuscular injection. Since there are few non-animal sources of the vitamin, vegans are advised to consume a dietary supplement or fortified foods for B12 intake, or risk serious health consequences. Children in some regions of developing countries are at particular risk due to increased requirements during growth coupled with diets low in animal-sourced foods. The US National Academy of Medicine updated estimated average requirements (EARs) and recommended dietary allowances (RDAs) for vitamin B12 in 1998. The EAR for vitamin B12 for women and men ages 14 and up is 2.0 μg/day; the RDA is 2.4 μg/d. RDA is higher than EAR to identify amounts that will cover people with higher-than-average requirements. RDA for pregnancy equals 2.6 μg/day. RDA for lactation equals 2.8 μg/d. For infants up to 12 months, the adequate intake (AI) is 0.4–0.5 μg/day. (AIs are established when there is insufficient information to determine EARs and RDAs.) For children ages 1–13 years, the RDA increases with age from 0.9 to 1.8 μg/day.
Sources: en.wikipedia.org
It is at this point where the size difference in human vs animal red blood cells can create inaccurate readings. Glucometers for humans were successfully used with pets long before animal-oriented meters were produced. A 2009 study directly compared readings from both types of glucometers to those of a chemistry analyzer. Neither glucometer's readings exactly matched those of the analyzer, but the differences of both were not clinically significant when compared to analyzer results. All glucometer readings need to be compared to same sample laboratory values to determine accuracy. Continuous glucose monitoring Some veterinarians are using continuous monitoring as part of the dog's treatment plan (2019). Sensors intended for humans, e.g. Abbot labs Freestyle Libre, can be applied and provide direct measurement of glucose levels eliminating the need for daily urine or blood checks.
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=== Advanced platelet-rich fibrin === Blood-derived growth factors have been used in medicine and oral surgery for more than twenty years with an abundance of scientific data supporting its role in soft and hard tissue regeneration. APRF, introduced by Dr. Joseph Choukroun, represents the fourth improved generation of such technology and has been widely used in the field of dentistry and oral surgery. Advantages of APRF include no risk of rejection or disease transmission (using your own blood) and improved healing (autogenous growth factors, hematopoietic or mesenchymal stem cells).
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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.
Selank is a seven-amino-acid peptide built from the tuftsin sequence plus a Pro-Gly-Pro tail. It is produced by chemical synthesis rather than extracted from a natural source. The free peptide is usually supplied as a lyophilised powder or in an aqueous formulation.