A practical reference on Neurotrophic factor: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-06-05 and is reviewed periodically as new material appears.
Animal studies have examined behaviour in tests of anxiety, memory retention and stress response, and several report changes in neurotrophic or neurotransmitter-related markers. The human evidence base is much smaller, consisting mainly of short trials conducted in Russia with limited reporting in English-language journals. Sample sizes are modest and outcome measures vary between studies, so the findings are best described as preliminary. Independent replication under modern trial standards has not been widely reported.
Outside its country of origin the compound is generally handled as a research chemical rather than an approved medicine. No regulatory approval from the United States Food and Drug Administration or the European Medicines Agency has been granted for human use. Identity and purity are normally checked by reverse-phase high-performance liquid chromatography, with mass spectrometry used to confirm the molecular mass. Lyophilised material is stored cold and desiccated, and repeated freeze-thaw cycles are avoided.
Published work on this peptide almost always uses intranasal delivery, with drops or a spray applied to the nasal mucosa. Some animal experiments have used subcutaneous or intraperitoneal injection, and a smaller number have compared routes directly. Oral administration is not a focus of the literature, because short peptides of this size are broken down by digestive enzymes and cross intestinal barriers poorly. How much of an intranasal dose reaches the bloodstream intact in humans remains an open question.
Reported pharmacological effects center on reduced anxiety-like behavior in animal models and on measures of memory and learning. Proposed contributing mechanisms include modulation of GABAergic signaling, shifts in monoamine turnover, and changes in the activity of enzymes that degrade neuropeptides. Effects on the expression of genes linked to neuroplasticity have also been described. No single molecular target is widely accepted, and whether the behavioral findings arise from one pathway or several remains an open question.
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.
| Property | Value | Notes |
|---|---|---|
| Common route | Intranasal | Also injected in some animal work |
| Solubility class | Freely soluble in water | Solid form is hygroscopic |
| Typical storage | About -20 degrees Celsius | Keep desiccated and dark |
| Purity method | Reverse-phase HPLC | Reported as area percent |
| Confirmatory method | Mass spectrometry | Verifies expected molecular mass |
Clinical evidence comes mainly from small studies conducted in Russia, several of which were open-label or lacked robust blinding. Reported outcomes include lower anxiety scores, changes in attention measures, and effects on asthenic states following illness. Sample sizes are typically in the tens of participants, and independent replication outside the region is scarce. Reviews published in English generally note the limited methodological quality of the underlying trials. Whether the compound produces clinically meaningful effects under rigorous conditions remains unresolved.
Proposed mechanisms center on modulation of the GABA system, but no single molecular target has been confirmed. Rodent studies report changes in GABA-A receptor expression and in the turnover of serotonin, dopamine, and norepinephrine in several brain regions. Increases in brain-derived neurotrophic factor and its receptor have also been described after repeated administration. These findings come largely from animal models, and the degree to which they describe human neurochemistry remains an open question. The mechanism is best characterized as multi-system and not fully resolved.
Dry powder is normally held at -20 degrees Celsius or lower, in a sealed container with desiccant and protection from light. Reconstituted solutions are usually kept at 2 to 8 degrees Celsius for short periods and frozen for longer ones. Proline residues at several positions are generally associated with some resistance to peptidase attack, but chemical stability still declines at neutral to alkaline pH and at elevated temperature. Exact shelf-life figures are product-specific and are not standardised across suppliers.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, with mass spectrometry used to confirm molecular mass and sequence information. Amino acid analysis and peptide mapping may supplement these methods. Certified reference standards are scarce, and many commercial lots are sold as research chemicals without a pharmacopoeial monograph. Regulatory treatment differs by country: Selank is a registered prescription medicine in Russia, while in the European Union and the United States it is not an approved drug and may fall under research-chemical or unapproved-product frameworks.
Selank is a hydrophilic peptide and dissolves readily in water and in aqueous buffers. The lyophilised powder is typically a white to off-white solid. Because short peptides are prone to hydrolysis and oxidation, handling benefits from limiting exposure to heat, moisture and strong light. Working solutions are commonly prepared in sterile water or saline, and repeated freeze-thaw cycles are avoided to reduce aggregation and loss of activity. These practices reflect general laboratory convention rather than published stability specifications.
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.
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.
==== Medical organizations ==== American Association for Anatomy, professional organization advancing anatomical sciences research and education Advanced Accelerator Applications, a radiopharmaceutical company
In June 1973, Gaddafi created a political ideology as a basis for the Popular Revolution: Third International Theory. This approach regarded both the US and the Soviet Union as imperialist and thus rejected Western capitalism as well as Marxist–Leninist atheism. In this respect, it was similar to the Three Worlds Theory developed by China's political leader Mao Zedong. As part of this theory, Gaddafi praised nationalism as a progressive force and advocated the creation of a pan-Arab state which would lead the Islamic and Third Worlds against imperialism. Gaddafi saw Islam as having a key role in this ideology, calling for an Islamic revival that returned to the origins of the Qur'an, rejecting scholarly interpretations and the Hadith; in doing so, he angered many Libyan clerics. During 1973 and 1974, his government deepened the legal reliance on sharia, for instance by introducing flogging as punishment for those convicted of adultery or homosexual activity. Gaddafi summarized Third International Theory in three short volumes published between 1975 and 1979, collectively known as The Green Book. Volume one was devoted to the issue of democracy, outlining the flaws of representative systems in favour of direct, participatory GPCs. The second dealt with Gaddafi's beliefs regarding socialism, while the third explored social issues regarding the family and the tribe. While the first two volumes advocated radical reform, the third adopted a socially conservative stance, proclaiming that while men and women were equal, they were biologically designed for different roles in life.
the damage to Mr. Banki's life brought about by his lengthy incarceration, occasioned by his confinement, cannot be measured only by the 22 months in which he lost his liberty and which he cannot get back".
=== Management of insulin resistance === The main methods of management involve exercise and diet change, in addition to treatment of PPID. The primary goal is reduction of weight in an obese animal. Diet changes include limiting pasture access and reducing or eliminating grain. Obese animals are often best maintained on a diet consisting of ration balancer and hay, fed at 1.5% body weight and decreased if needed. Feed should be selected based on low nonstructural carbohydrate (NSC) levels. Hay NSC levels may be reduced by soaking it in cold water for 30 minutes. Exercise is increased in nonlaminitic horses. Animals resistant to weight loss, despite diet and exercise changes, can be placed on levothyroxine to increase metabolism. Metformin can also be used to reduce glucose absorption through the intestinal tract.
==== 16th century ==== The first records relating to the Cossack villages: the "stanitsas", date back to 1549. In the year 1552 Don Cossacks under the command of Ataman Susar Fedorov joined the Army of Ivan the Terrible during the Siege of Kazan in 1552. On 2 June 1556 the Cossack regiment of Ataman Lyapun Filimonov, together with the Army of Moscovits comprising strelets, conquered and annexed the Astrakhan Khanate. During the reign of Ivan the Terrible (Ivan IV), the ataman Yermak Timofeyevich went on an expedition to conquer Siberia. After defeating Khan Kuchum in the fall of 1582 and occupying Isker, the capital of the Siberian Khanate, Yermak sent a force of Cossacks down the Irtysh in the winter of 1583. The detachment, led by Bogdan Bryazga (according to other sources, the Cossack chieftain Nikita Pan) passed through the lands of the Konda-Pelym Voguls and reached the walls of the town of Samarovo. Surprised by the Cossack attack, the Ostyaks surrendered. In the autumn of 1585, shortly after Yermak's death, Cossacks led by voevoda (army commander) Ivan Mansurov founded the first Russian fortified town in Siberia, Obskoy, at the mouth of the Irtysh river on the right bank of the Ob river. The Mansi and Khanty lands thus became part of the Russian state, finally secured by the founding of the cities of Pelym and Berezov in 1592 and Surgut in 1594. As a result of Yermak's expedition, Russia was able to annex Siberia.
Sources: en.wikipedia.org
=== Physical properties === Elemental magnesium is a gray-white lightweight metal, two-thirds the density of aluminium. Magnesium has the lowest melting (923 K (650 °C)) and the lowest boiling point (1,363 K (1,090 °C)) of all the alkaline earth metals. Pure polycrystalline magnesium is brittle and easily fractures along shear bands. It becomes much more malleable when alloyed with small amounts of other metals, such as 1% aluminium. The malleability of polycrystalline magnesium can also be significantly improved by reducing its grain size to about 1 μm or less.
Gee highlighted particular success with a child fed "a quart of the best Dutch mussels daily"; the child could not bear this diet for more than one season. Christian Archibald Herter, an American physician, wrote a book in 1908 on children with coeliac disease, which he called "intestinal infantilism". He noted their growth was retarded and that fat was better tolerated than carbohydrate. The eponym Gee-Herter disease was sometimes used to acknowledge both contributions. Sidney V. Haas, an American paediatrician, reported positive effects of a diet of bananas in 1924. This diet remained in vogue until the actual cause of coeliac disease was determined. While a role for carbohydrates had been suspected, the link with wheat was not made until the 1940s by the Dutch paediatrician Willem Karel Dicke. Clinical improvement of his patients during the Dutch famine of 1944–1945 (during which flour was scarce) likely contributed to his discovery. Dicke noticed that the shortage of bread led to a significant drop in the death rate among children affected by coeliac disease from greater than 35% to essentially zero. He also reported that once wheat was again available after the conflict, the mortality rate soared to previous levels. The link with the gluten component of wheat was made in 1952 by a team from Birmingham, England. Villous atrophy was described by British physician John W. Paulley in 1954 on samples taken at surgery. This encouraged biopsy samples taken by endoscopy. Throughout the 1960s, other features of coeliac disease were elucidated.
== Structure == Epithelial tissue cells can adopt shapes of varying complexity from polyhedral to scutoidal to punakoidal. They are tightly packed and form a continuous sheet with almost no intercellular spaces. All epithelia is usually separated from underlying tissues by an extracellular fibrous basement membrane. The lining of the mouth, lung alveoli and kidney tubules are all made of epithelial tissue. The lining of the blood and lymphatic vessels are of a specialised form of epithelium called endothelium.
Shafts were drilled at the site before the test in order to accelerate sample collection after explosion, so that explosion would expel radioactive material from the epicenter through the shafts and to collecting volumes near the surface. This method was tried in two tests and instantly provided hundreds of kilograms of material, but with actinide concentration three times lower than in samples obtained after drilling. Whereas such method could have been efficient in scientific studies of short-lived isotopes, it could not improve the overall collection efficiency of the produced actinides. Though no new elements (except einsteinium and fermium) could be detected in the nuclear test debris, and the total yields of transuranics were disappointingly low, these tests did provide significantly higher amounts of rare heavy isotopes than previously available in laboratories.
Witnesses included FDA officials. They looked into several areas: the delay in reporting by Menu Foods, the lack of federal inspections of pet food facilities, and incomplete reporting by the FDA since the start of the recall. During the hearing Senators Durbin and Byrd criticized the government's response during the recall. Durbin specifically criticized the lack of any regular inspection practices or quality control with regards to pet food safety. Senator Kohl criticized the FDA's communication to the public about recalled foods, noting that volunteer websites had more detailed and easier-to-access information about the extent of the problem and which specific foods are of concern than FDA's online resources which Kohl said was contradictory of itself at times, and which the FDA official giving testimony admitted to being difficult to navigate. On 18 April 2007, Senator Durbin and Representative DeLauro met with US FDA Commissioner von Eschenbach to discuss the additional rice protein recalls and learned that the Chinese government was blocking outside attempts to investigate the contamination. In response, they sent a letter to Zhou Wenzong, China's Ambassador to the United States saying in part that "contaminated batches of wheat gluten and rice protein responsible for these events were imported from China" and that "no level of melamine should be found in pet or human food" and asking for visas for inspectors from the United States.
Sources: en.wikipedia.org
Most published work uses intranasal application, either as drops or as a nasal spray. Injection routes appear in a smaller set of animal experiments. Oral use is uncommon in the literature because peptide breakdown and poor absorption limit this route.
Reported human trials are few, brief and originate mainly from one country. They describe effects on anxiety-related measures, but sample sizes are small and reporting is limited. The results are widely regarded as preliminary rather than confirmed.
Reverse-phase liquid chromatography is used to assess purity and separation of related impurities. Mass spectrometry confirms that the observed molecular mass matches the expected peptide. A certificate of analysis from the supplier is the usual document of record.
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.