Tuftsin comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2026-05-09. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Enzymatic stability motivates the extra three residues at the carboxyl end. Native tuftsin is cleaved quickly by circulating aminopeptidases and carboxypeptidases, which limits its duration of action and its usefulness as a tool compound. Extending the chain with proline-rich segments is a common design tactic because proline constrains the backbone and slows proteolysis. The same Pro-Gly-Pro motif appears in other Russian-developed peptides of the era. Whether the full seven-residue chain is required for activity, or whether it acts mainly as a prodrug releasing tuftsin, remains unresolved.
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.
| Property | Value | Notes |
|---|---|---|
| Principal proposed target | GABA-A receptor complex | Hypothesis derived mainly from animal pharmacology |
| Common behavioral assay | Elevated plus maze | Rodent test for anxiety-like behavior |
| Reported molecular marker | Hippocampal BDNF expression | Measured by immunoassay or mRNA quantification |
| Typical dosing route | Intranasal | Chosen to reduce first-pass metabolism |
| Reported plasma half-life | Minutes | Based on limited peptide stability data |
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.
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.
Quality assessment of Selank samples typically combines purity determination with identity confirmation and counter-ion analysis. Purity is usually reported as a percentage by chromatographic area, with values above 95 percent often quoted for research-grade material. Water content and residual solvents are checked in lyophilized batches because they affect both stability and accurate mass determination. A reported purity figure does not by itself establish that a sample is the intended sequence, so orthogonal methods are needed to rule out sequence isomers or truncation products.
Characterization of Selank in laboratory settings relies on standard peptide analytical techniques. Reverse-phase high-performance liquid chromatography separates the peptide from related impurities and degradation products, while mass spectrometry confirms molecular identity through accurate mass measurement. Amino acid analysis and peptide sequencing verify the primary structure when reference material is unavailable. Because Selank is a short chain, fragmentation-based analysis produces a diagnostic ion pattern that supports confident identification.
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.
=== Hemorrhagic Infiltration === Many authors state that blood and its breakdown products acting as foreign-body substance in the subarachnoid space produce local adhesive arachnoiditis with no symptoms, but it also can create cystic degeneration. The subarachnoid space abhors all foreign body substances. Even the presence of injected air is considered to be a "foreign body". Blood definitely is considered a foreign body, particularly in its breakdown products. Repeated exposure to foreign body substances in the subarachnoid space or spinal injury can initiate auto-immune amnestic reactions which may potentiate and magnify the ongoing inflammatory process causing cystic cavitation in spinal tissue.
On the day of the surgery, the patient arrives to either a hospital or an outpatient surgery center, where the procedure will be performed. The patient is given a brief physical examination by the surgical team and is taken to the operating room. In the operating room, the patient lies down on an operating table and is either given general anesthesia, or local anesthesia and a sedative. With anesthesia induced, the surgical team prepares the eye to be operated on and drapes the face around the eye. An eyelid speculum is placed to keep the lids open, and some lubrication is placed on the eye to prevent drying. In children, a metal ring is stitched to the sclera which will provide support of the sclera during the procedure.
== Bibliography == Bagnall, K. W. (1962) [1962]. "The Chemistry of Polonium". Advances in Inorganic Chemistry and Radiochemistry. Vol. 4. New York: Academic Press. pp. 197–226. doi:10.1016/S0065-2792(08)60268-X. ISBN 978-0-12-023604-6. Retrieved 14 June 2012. {{cite book}}: ISBN / Date incompatibility (help) Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth–Heinemann. ISBN 978-0080379418.
Biotechnology in the general sense has been an important part of biology since the late 19th century. With the industrialization of brewing and agriculture, chemists and biologists became aware of the great potential of human-controlled biological processes. In particular, fermentation proved a great boon to chemical industries. By the early 1970s, a wide range of biotechnologies were being developed, from drugs like penicillin and steroids to foods like Chlorella and single-cell protein to gasohol—as well as a wide range of hybrid high-yield crops and agricultural technologies, the basis for the Green Revolution.
Adverse effects have been documented from vitamin B6 dietary supplements, but never from food sources. Even though it is a water-soluble vitamin and is excreted in the urine, doses of pyridoxine in excess of the dietary upper limit (UL) over long periods cause painful and ultimately irreversible neurological problems. The primary symptoms are pain and numbness of the extremities. In severe cases, motor neuropathy may occur with "slowing of motor conduction velocities, prolonged F wave latencies, and prolonged sensory latencies in both lower extremities", causing difficulty in walking. Sensory neuropathy typically develops at doses of pyridoxine in excess of 1,000 mg per day. As noted above, in 2023 the European Food Safety Commission set an adult UL at 12 mg/day. While Australia has set an upper limit of 50 mg/day, the Therapeutic Goods Administration requires a label warning about peripheral neuropathy if the daily dose is predicted to exceed 10 mg/day.
Sources: en.wikipedia.org
Field desorption ionization was first reported by Beckey in 1969. In field ionization, a high-potential electric field is applied to an emitter with a sharp surface, such as a razor blade, or more commonly, a filament from which tiny "whiskers" have been grown. This produces a very high electric field in which electron tunneling can result in ionization of gaseous analyte molecules. FI produces mass spectra with little or no fragmentation, dominated by molecular radical cations M+. and occasionally protonated molecules
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Drugs in the US were largely unregulated until the early 20th century. Opium had been used to relieve pain since the Revolutionary War, but the use of opiates in the civilian population began to increase dramatically in the late 1800s, and cocaine use became prevalent. Alcohol consumption steadily grew, as did the temperance movement, well-supported by the middle class, promoting moderation or abstinence. The practice of smoking cannabis began to be noticed in the early 1900s. State and local governments began enacting drug laws in the mid-1800s. Under the US Constitution, the authority to control dangerous drugs exists separately at both the federal and state level. Federal drug legislation arrived after the turn of the century.
== External links == Atrial+Natriuretic+Factor at the U.S. National Library of Medicine Medical Subject Headings (MeSH) Human NPPA genome location and NPPA gene details page in the UCSC Genome Browser. Overview of all the structural information available in the PDB for UniProt: P01160 (Natriuretic peptides A) at the PDBe-KB.
Sources: en.wikipedia.org
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.
Behavioral endpoints include time spent in open arms of the elevated plus maze and avoidance latencies. Biochemical endpoints include BDNF concentration, cytokine levels, and monoamine metabolite ratios in brain tissue.
Most published studies are small, originate from a limited number of laboratories, and lack independent replication. Dose-response relationships, measured brain exposure, and long-term outcomes are not well characterized.
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.