If you have been reading about Selank and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-08-01. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
Tuftsin, the parent structure, is a naturally occurring immunomodulatory tetrapeptide released from the Fc region of immunoglobulin G by spleen enzymes. Selank extends this four-residue sequence with three additional amino acids. The stated rationale is that the added tail slows enzymatic breakdown and may influence receptor interactions. How the full heptapeptide behaves at the molecular level is not firmly established, and proposed mechanisms often involve indirect modulation of neurotransmitter or immune signaling rather than a single defined target.
Selank is a synthetic heptapeptide developed in Russia. Its sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, a seven-residue chain built around the natural tetrapeptide tuftsin. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences first described the compound in the mid-1990s. The design combined the tuftsin core with an added Pro-Gly-Pro tail, a modification intended to extend the molecule's stability in biological fluids. Published work on the peptide has appeared mainly in Russian-language journals.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Tuftsin analogue with a C-terminal Pro-Gly-Pro tail |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Abbreviated TKPRPGP in most catalogues |
| Molecular mass | About 752 Da | Value for the free peptide |
| Solubility | Freely soluble in water | Aqueous solutions are kept cold and used promptly |
| Typical storage | -20 °C, dry, protected from light | Applies to the lyophilised powder before reconstitution |
Selank is not a naturally occurring peptide and has no known endogenous counterpart in human physiology. Russian-language sources frequently call it TP-7, while English-language sources use the name Selank almost exclusively. Database indexing is uneven, partly because early reports appeared in regional journals that are not widely cataloged. Some summaries describe the material as a tuftsin analog and others as a synthetic heptapeptide; the labels overlap rather than conflict. Citing the primary sequence resolves ambiguity more reliably than the research or trade name alone.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, written TKPRPGP in one-letter notation. Its structure consists of the immunomodulatory tetrapeptide tuftsin, Thr-Lys-Pro-Arg, extended at the carboxyl terminus by a Pro-Gly-Pro segment. The molecular formula is commonly given as C33H57N11O9, corresponding to a monoisotopic mass near 751.4 Da and an average molecular mass near 751.9 Da. All seven residues are proteinogenic amino acids, and the molecule carries no modified side chains or non-natural linkages.
The primary structure of Selank is Thr-Lys-Pro-Arg-Pro-Gly-Pro, corresponding to the molecular formula C33H57N11O9 and a monoisotopic mass of roughly 751.9 daltons. The N-terminal threonine and the arginine residue in the fourth position are shared with tuftsin, which carries the sequence Thr-Lys-Pro-Arg. The three additional residues at the C-terminus, Pro-Gly-Pro, extend the chain and are associated with greater resistance to enzymatic degradation. This extension also separates Selank from the shorter parent peptide.
Naming conventions place Selank in the same research family as Semax, another Russian-developed peptide investigated for cognitive effects. The two compounds share a lineage but differ in sequence and in the biological systems proposed as their targets. Semax descends from ACTH fragments, whereas Selank descends from tuftsin. Publications sometimes identify Selank by its full peptide sequence or by laboratory codes rather than one uniform trade name. Because replication outside Russia is limited, reports on its properties are best read alongside the study design and the purity of the material tested.
Selank is a synthetic heptapeptide developed in Russia during the 1990s. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences designed it as a stabilized analog of tuftsin, a naturally occurring immunomodulatory tetrapeptide. The compound has been studied primarily for its reported anxiolytic and nootropic effects. It remains largely unknown in Western pharmacology and is not approved as a medicine by major regulators such as the FDA or the EMA.
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.
Nuclear fission is a reaction in which the nucleus of an atom splits into two or more smaller nuclei. The fission process often produces neutrons and gamma rays, and releases a very large amount of energy even by the energetic standards of radioactive decay. The free energy released by the fission of one uranium-235 atom is about 100 million times the energy released by burning one carbon atom in air to produce CO2. Nuclear fission was discovered by chemists Otto Hahn and Fritz Strassmann and physicists Lise Meitner and Otto Robert Frisch. Hahn and Strassmann proved that a fission reaction had taken place on 19 December 1938, and Meitner and her nephew Frisch explained it theoretically in January 1939. Frisch named the process "fission" by analogy with biological fission of living cells. In their second publication on nuclear fission in February 1939, Hahn and Strassmann predicted the existence and liberation of additional neutrons during the fission process, opening up the possibility of a nuclear chain reaction by assembling a critical mass of fissile material. For heavy nuclides, it is an exothermic reaction which releases large amounts of energy both as electromagnetic radiation and as kinetic energy of the fragments (heating the bulk material where fission takes place). Like nuclear fusion, for fission to produce energy, the total binding energy of the resulting elements must be greater than that of the starting element. The fission barrier must also be overcome.
Roles for the ER chaperones GRP94, EDEM and BiP have been proposed prior to the 'dislocation' of RTA from the ER lumen to the cytosol in a manner that uses components of the endoplasmic reticulum-associated protein degradation (ERAD) pathway. ERAD normally removes misfolded ER proteins to the cytosol for their destruction by cytosolic proteasomes. Dislocation of RTA requires ER membrane-integral E3 ubiquitin ligase complexes, but RTA avoids the ubiquitination that usually occurs with ERAD substrates because of its low content of lysine residues, which are the usual attachment sites for ubiquitin. Thus, RTA avoids the usual fate of dislocated proteins (destruction that is mediated by targeting ubiquitinylated proteins to the cytosolic proteasomes). In the mammalian cell cytosol, RTA then undergoes triage by the cytosolic molecular chaperones Hsc70 and Hsp90 and their co-chaperones, as well as by one subunit (RPT5) of the proteasome itself, that results in its folding to a catalytic conformation, which de-purinates ribosomes, thus halting protein synthesis.
Unlike the other major plant hormones, ethylene is a gas and a very simple organic compound, consisting of just six atoms. It forms through the breakdown of methionine, an amino acid which is in all cells. Ethylene has very limited solubility in water and therefore does not accumulate within the cell, typically diffusing out of the cell and escaping the plant. Its effectiveness as a plant hormone is dependent on its rate of production versus its rate of escaping into the atmosphere. Ethylene is produced at a faster rate in rapidly growing and dividing cells, especially in darkness. New growth and newly germinated seedlings produce more ethylene than can escape the plant, which leads to elevated amounts of ethylene, inhibiting leaf expansion (see hyponastic response). As the new shoot is exposed to light, reactions mediated by phytochrome in the plant's cells produce a signal for ethylene production to decrease, allowing leaf expansion. Ethylene affects cell growth and cell shape; when a growing shoot or root hits an obstacle while underground, ethylene production greatly increases, preventing cell elongation and causing the stem to swell. The resulting thicker stem is stronger and less likely to buckle under pressure as it presses against the object impeding its path to the surface. If the shoot does not reach the surface and the ethylene stimulus becomes prolonged, it affects the stem's natural geotropic response, which is to grow upright, allowing it to grow around an object.
=== Background === After World War I, the United States pursued a policy of isolationism and declined to join the League of Nations in 1919. Roosevelt had been a supporter of the League of Nations but, by 1935, he told his foreign policy adviser Sumner Welles: "The League of Nations has become nothing more than a debating society, and a poor one at that!". Roosevelt criticized the League for representing the interests of too many nations. He came to favor an approach to global peace secured through the unified efforts of the world's great powers, rather than through the Wilsonian notions of international consensus and collaboration that guided the League of Nations. The idea that great powers should "police" the world had been discussed by President Roosevelt as early as August 1941, during his first meeting with British Prime Minister Winston Churchill. When the Atlantic Charter was issued, Roosevelt had ensured that the charter omitted mentioning any American commitment towards the establishment of a new international body after the war. He was reluctant to publicly announce his plans for creating a postwar international body, aware of the risk that the American people might reject his proposals, and he did not want to repeat Woodrow Wilson's struggle to convince the Senate to approve American membership in the League of Nations. Roosevelt's proposal was to create a new international body led by a "trusteeship" of great powers that would oversee smaller countries. In September 1941, he wrote:
==== Electronics ==== An aqueous solution of copper(II) sulfate is often used as the resistive element in liquid resistors. In electronic and microelectronic industry a bath of CuSO4·5H2O and sulfuric acid (H2SO4) is often used for electrodeposition of copper.
Sources: en.wikipedia.org
== Vendors == To list on a market, a vendor may have undergone an application process via referral, proof of reputation from another market or given a cash deposit to the market. Many vendors list their wares on multiple markets, ensuring they retain their reputation even should a single market place close. Grams (closed December 2017) had launched "InfoDesk" to allow central content and identity management for vendors as well as PGP key distribution. Meanwhile, individual law enforcement operations regularly investigate and arrest individual vendors and those purchasing significant quantities for personal use. A February 2016 report suggested that a quarter of all DNM purchases were for resale.
=== Biomedical imaging === There are many applications for iron-oxide based nanoparticles in concert with magnetic resonance imaging. Magnetic CoPt nanoparticles are being used as an MRI contrast agent for transplanted neural stem cell detection.
=== Cancer treatment === Some preclinical and clinical research suggests that some beta blockers may be beneficial for cancer treatment. However, other studies do not show a correlation between cancer survival and beta blocker use. Also, a 2017 meta-analysis failed to show any benefit for the use of beta blockers in breast cancer.
Induces endometrial secretory transformation in preparation for pregnancy (>5 ng/mL) Prevents estrogen-induced endometrial hyperplasia and increased endometrial cancer risk Maintains pregnancy via effects in endometrium (with withdrawal resulting in miscarriage) Reduces amount and fibrosity of cervical mucus and causes cervix to become firmer and more tightly closed Controls motility and composition of fluid in the fallopian tubes Reduced cornification and maturation of the vaginal lining Causes water retention in the breasts resulting in temporary enlargement during the menstrual cycle Mediates lobuloalveolar development of the breasts necessary for lactation Suppresses lactation initiation and triggers lactation upon withdrawal (as with parturition) Maintains skin health, integrity, appearance, and hydration and slows the rate of aging of the skin Modulates brain function, with effects on mood, emotionality, and sexuality, as well as cognition and memory Exerts negative feedback on the hypothalamic–pituitary–gonadal axis (HPG axis) by suppressing the secretion of the gonadotropins FSH and LH from the pituitary gland (including the mid-cycle gonadotropin surge), thereby inhibiting gonadal sex hormone production as well as ovulation and fertility (>2 ng/mL) Increases basal body temperature (by 0.3–0.6 °C (0.5–1.0 °F) relative to preovulation) via the hypothalamus (>4 ng/mL) Reduces hot flashes via the hypothalamus Stimulates respiration via the hypothalamus and/or respiratory center Influences the risk and/or progression of hormone-sensitive cancers including breast cancer and endometrial cancer Many of the effects of progesterone require estrogen, as estrogens prime tissues for progesterone by inducing expression of the PRs. The PRs are induced in the breasts by estrogens, and for this reason, it is assumed that progestogens cannot mediate breast changes in the absence of estrogens. Progesterone also lowers blood pressure and reduces water and salt retention among other effects via its antimineralocorticoid activity. Progesterone can produce sedative, hypnotic, anxiolytic, euphoric, cognitive-, memory-, and motor-impairing, anticonvulsant, and even anesthetic effects via formation of sufficiently high concentrations of its neurosteroid metabolites and consequent GABAA receptor potentiation in the brain.
Jens Juul Holst (born 31 August 1945) is a Danish physician and physiologist. He is known for discovering and describing the hormone glucagon-like peptide-1 (GLP-1), a hormone in the gut that plays an important role in the onset and development of Type 2 diabetes. In collaboration with researcher and author Arne Astrup, he discovered that GLP-1 acts as a satiety hormone in humans. In 2020, he was awarded the Warren Alpert Foundation Prize along Daniel J. Drucker and Joel F. Habener. In 2021, he was awarded the Canada Gairdner International Award along Daniel J. Drucker, Joel F. Habener, and Mary-Claire King. He was also awarded the Banting Medal by the American Diabetes Association (ADA). In 2024, he was awarded the Princess of Asturias Awards for Technical and Scientific Research along Daniel J. Drucker, Jeffrey M. Friedman, Joel F. Habener, and Svetlana Mojsov. In 2024, he received the Tang Prize in the category of "Biopharmaceutical Science", and the BBVA Foundation Frontiers of Knowledge Award in the category "Biology and Biomedicine". In 2025, he received the Breakthrough Prize in Life Sciences alongside Daniel Drucker, Joel Habener, Svetlana Mojsov, and Lotte Bjerre Knudsen).
Sources: en.wikipedia.org
ATPases (EC 3.6.1.3, Adenosine 5'-TriPhosphatase, adenylpyrophosphatase, ATP monophosphatase, triphosphatase, ATP hydrolase, adenosine triphosphatase) are a class of enzymes that catalyze the decomposition of ATP into ADP and a free phosphate ion or the inverse reaction. This dephosphorylation reaction releases energy, which the enzyme (in most cases) harnesses to drive other chemical reactions that would not otherwise occur. This process is widely used in all known forms of life. Some such enzymes are integral membrane proteins (anchored within biological membranes), and move solutes across the membrane, typically against their concentration gradient. These are called transmembrane ATPases.
The Rhodesian Land Tenure Act was introduced the same year, which ostensibly introduced parity by reducing the amount of land reserved for white ownership to the same 45 million acres as for blacks: in practice, the most fertile farmlands remained in white hands, and some farmers took advantage by shifting their boundaries into black-populated territories, often without notifying others, thereby necessating government evictions. In 1977, the party had a schism in which the more hardline wing broke off to form the Rhodesian Action Party (RAP), which opposed Smith's proposals to negotiate a settlement with black nationalist leaders. In the elections leading to the country's independence in 1980, as the Republic of Zimbabwe, the RF won all 20 parliamentary seats reserved for whites in the power-sharing agreement that it had forged. On 6 June 1981, the party changed its name to the Republican Front, and on 23 July 1984, that party became the Conservative Alliance of Zimbabwe (CAZ) and opened its membership to Zimbabweans of all colours and all ethnic groups. Eleven of its 20 parliamentarians defected over the following four years, but the party again won 15 of the 20 parliamentary seats reserved for whites in the 1985 election. In October 1987, the ruling government of Robert Mugabe officially abolished all reserved seats for whites. When these were abolished, many white MPs became independents or joined the ruling ZANU–PF party.
== Interactions == GSTP1 has been shown to interact with Fanconi anemia, complementation group C and MAPK8. GST-Pi is expressed in many human tissues, particularly in the biliary tree, renal distal convoluted tubules and lungs.
== Risks == The use of sedative medications in older people generally should be avoided. These medications are associated with poorer health outcomes, including cognitive decline, fall, and bone fractures. Sedatives and hypnotics should also be avoided in people with dementia, according to the clinical guidelines known as the Medication Appropriateness Tool for Comorbid Health Conditions in Dementia (MATCH-D). The use of these medications can further impede cognitive function for people with dementia, who are also more sensitive to side effects of medications. Some hypnotics, such as low-dose doxepin, melatonin receptor agonists, and orexin receptor antagonists, may be safer and more appropriate in older adults however.
Sources: en.wikipedia.org
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.
Tuftsin is a natural tetrapeptide derived from the Fc portion of immunoglobulin G. Selank retains that tetrapeptide at its N-terminus and adds three residues to improve resistance to enzymatic breakdown. The relationship is structural, and the two molecules are not interchangeable in experimental work.
It holds a product registration in Russia for intranasal use as an anxiolytic. Registrations of that kind are not automatically accepted by regulators elsewhere. In most other countries it is treated as an unapproved substance or a research material.
Selank is a synthetic peptide made of seven amino acids. It is modeled on tuftsin, a natural tetrapeptide, with an added three-residue tail. It is not a small-molecule drug.