heptapeptide 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.
Last reviewed on 2026-06-06. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Reverse-phase high-performance liquid chromatography with ultraviolet detection near 214 nanometres is the standard purity method. Mass spectrometry, typically electrospray ionisation, confirms identity through the expected mass-to-charge pattern. Amino acid analysis can verify composition independently. Chiral purity requires separate techniques such as derivatisation followed by chromatographic separation, and such data are rarely reported for research-grade material.
Quantification in biological matrices relies on liquid chromatography coupled to tandem mass spectrometry with stable-isotope internal standards. Low plasma concentrations and adsorption to container surfaces both complicate measurement. Solid-phase extraction is often needed to reduce matrix interference before injection. Reported limits of quantification differ widely between laboratories, which makes direct comparison of pharmacokinetic results difficult and limits meta-analysis.
Peptide bonds are vulnerable to protease attack, and Selank is no exception. Measured half-life in serum is short, on the order of minutes in several reports, which explains why intranasal administration is the common route described in the literature. Absorption across the nasal mucosa partially bypasses first-pass hepatic metabolism. Quantitative data on human bioavailability remain limited and are difficult to compare across studies.
| 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 |
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.
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.
Pharmacokinetic data are limited. Like most short peptides, Selank is vulnerable to plasma and tissue peptidases, and its measured half-life in circulation is short, on a minutes scale. The Pro-Gly-Pro tail slows this degradation but does not eliminate it. Intranasal administration is the route described in most reports, with absorption through the nasal mucosa and a hypothesized path into the central nervous system that avoids the blood-brain barrier. Direct measurements of human brain exposure are unavailable, so distribution claims rest on inference from animal work.
== Management of intoxication == Management of PCP intoxication mostly consists of supportive care – controlling breathing, circulation, and body temperature – and, in the early stages, treating psychiatric symptoms. Benzodiazepines, such as lorazepam, are the drugs of choice to control agitation and seizures (when present). Typical antipsychotics such as phenothiazines and haloperidol have been used to control psychotic symptoms, but may produce many undesirable side effects – such as dystonia – and their use is therefore no longer preferred; phenothiazines are particularly risky, as they may lower the seizure threshold, worsen hyperthermia, and boost the anticholinergic effects of PCP. If an antipsychotic is given, intramuscular haloperidol has been recommended. Forced acid diuresis (with ammonium chloride or, more safely, ascorbic acid) may increase the clearance of PCP from the body, and was somewhat controversially recommended in the past as a decontamination measure. However, it is now known that only around 10% of a dose of PCP is removed by the kidneys, which would make increased urinary clearance of little consequence; furthermore, urinary acidification is dangerous, as it may induce acidosis and worsen rhabdomyolysis (muscle breakdown), a not-unusual manifestation of PCP toxicity.
After a median follow-up of 40 months, the trial demonstrated a statistically significant improvement in IDFS in patients who received trastuzumab emtansine compared with those who received trastuzumab (HR 0.50; 95% CI: 0.39, 0.64; p<0.0001). Overall survival data were not mature at the time of the IDFS analysis.
=== Wild birds === Wildlife, including wild and migratory birds, serve as indicators of ecosystem health. They act as a reservoir for zoonotic diseases and antimicrobial-resistant organisms. Birds are a key link between the transmission of zoonotic diseases to human populations. By the same token, increased contact between wild birds and human populations (including domesticated animals), has increased the amount of anti-microbial resistance (AMR) to the bird population. The introduction of AMR to wild birds positively correlates with human pollution and increased human contact. Additionally, wild birds can participate in horizontal gene transfer with bacteria, leading to the transmission of antibiotic-resistant genes (ARG). For simplicity, wild bird populations can be divided into two major categories, wild sedentary birds and wild migrating birds. Wild sedentary bird exposure to AMR is through increased contact with densely populated areas, human waste, domestic animals, and domestic animal/livestock waste. Especially if they are predators, wild, sedentary birds can come into contact with prey that interact more closely with humans. Wild migrating birds interact with sedentary birds in different environments along their migration route. This increases the rate and diversity of AMR across varying ecosystems. Neglect of wildlife in the global discussions surrounding health security and AMR, creates large barriers to true AMR surveillance.
== Regulation of TIMP expression == Transcription of this gene is highly inducible in response to many cytokines and hormones. In addition, the expression from some but not all inactive X chromosomes suggests that this gene inactivation is polymorphic in human females. This gene is located within intron 6 of the synapsin I gene and is transcribed in the opposite direction. In adrenocortical cells the trophic hormone ACTH induces expression of TIMP-1 and the increase in TIMP expression is also associated with decreased collagenase activity. Increased expression of TIMP1 has been found to be associated with worse prognosis of various tumors, such as laryngeal carcinoma or melanoma.
The kynurenine pathway is a metabolic pathway leading to the production of nicotinamide adenine dinucleotide (NAD+). Metabolites involved in the kynurenine pathway include tryptophan, kynurenine, kynurenic acid, xanthurenic acid, quinolinic acid, and 3-hydroxykynurenine. The kynurenine pathway is responsible for about 95% of total tryptophan catabolism. Disruption in the pathway is associated with certain genetic and psychiatric disorders.
Sources: en.wikipedia.org
== Early life and biography == Kearon was born on 18 July 1961 in Carlisle, England. He spent part of his youth in Saudi Arabia, where his father worked. After his father's death when Kearon was 19, he gave up on additional formal education and entered the workforce. His first job was working for a Member of Parliament, and he later worked for Nestlé in England, Saudi Arabia, and the United States. He owned his own public affairs consulting company before beginning his full-time service in the church. Kearon was first introduced to the church in the mid-1980s while staying with a Latter-day Saint family in Laguna, California. He has said that the family "lived a joyful existence founded on service." He met missionaries in London several years later and began learning about the church, and was baptized on Christmas Eve, 1987.
The synthesis of glucose established the structure of organic material and consequently formed the first definitive validation of Jacobus Henricus van 't Hoff's theories of chemical kinetics and the arrangements of chemical bonds in carbon-bearing molecules. Between 1891 and 1894, Fischer established the stereochemical configuration of all the known sugars and correctly predicted the possible isomers, applying the Van 't Hoff equation of asymmetrical carbon atoms. The names initially referred to the natural substances. Their enantiomers were given the same name with the introduction of systematic nomenclatures, taking into account absolute stereochemistry (e.g. Fischer nomenclature, d/l nomenclature). For the discovery of the metabolism of glucose Otto Fritz Meyerhof received the Nobel Prize in Physiology or Medicine in 1922. Hans von Euler-Chelpin was awarded the Nobel Prize in Chemistry along with Arthur Harden in 1929 for their "research on the fermentation of sugar and their share of enzymes in this process". In 1947, Bernardo Houssay (for his discovery of the role of the pituitary gland in the metabolism of glucose and the derived carbohydrates) as well as Carl and Gerty Cori (for their discovery of the conversion of glycogen from glucose) received the Nobel Prize in Physiology or Medicine. In 1970, Luis Leloir was awarded the Nobel Prize in Chemistry for the discovery of glucose-derived sugar nucleotides in the biosynthesis of carbohydrates.
Progesterone can be administered by subcutaneous injection, with Prolutex, an aqueous solution of progesterone marketed in Europe, being intended for once-daily administration by this route. This formulation is rapidly absorbed and has been found to result in higher peak levels of progesterone relative to progesterone in oil solution by intramuscular injection. In addition, subcutaneous injection of progesterone is considered to be easier, safer due less risk of injection site reactions, and less painful compared to intramuscular injection of progesterone. The elimination half-life of this formulation is 13 to 18 hours, compared to 20 to 28 hours for intramuscular injection of progesterone in oil solution.
TC# 2.A.3 - Amino Acid-Polyamine-Organocation (APC) Superfamily TC# 2.A.18 - Amino Acid/Auxin Permease (AAAP) Family TC# 2.A.23 - Dicarboxylate/Amino Acid:Cation (Na+ or H+) Symporter (DAACS) Family TC# 2.A.26 - Branched Chain Amino Acid:Cation Symporter (LIVCS) Family TC# 2.A.42 - Hydroxy/Aromatic Amino Acid Permease (HAAAP) Family TC# 2.A.78 - Branched Chain Amino Acid Exporter (LIV-E) Family TC# 2.A.95 - 6TMS Neutral Amino Acid Transporter (NAAT) Family TC# 2.A.118 - Basic Amino Acid Antiporter (ArcD) Family TC# 2.A.120 - Putative Amino Acid Permease (PAAP) Family
Sources: en.wikipedia.org
== Commercial release == "Valley Girl" was picked up by KROQ-FM, who obtained an acetate disc before release. Zappa praised the station's original programming but feared it would lead to others copying it, adding, "I would hate for it to become another service, freeze-dried to other stations." Moon was a regular KROQ listener and persuaded the station to play the track during an interview. There was an immediate response from the public, and the song began receiving regular airplay. The song was Zappa's only Top 40 single in North America, peaking at #32 on the U.S. Billboard Hot 100 chart and at #18 on the Canadian RPM Top Singles chart in September 1982, although he had charted hits in other parts of the world. The song was also included on the compilation album Strictly Commercial (1995). In the U.S. the B-side was "You Are What You Is", but in other territories it was "Teen-Age Prostitute." Promotional copies contained the album and single versions of the song.
However, light intensity walking is an effective way to help control casual glucose level (CGL), but a minimum of 6000 steps must be achieved daily to have consistent effectiveness in controlling CGL.Nevertheless, there is no significant correlation between light intensity walking and HbA1c, therefore regular moderate intensity exercise is advised, specifically aerobic exercise has been proven to improve both fasting and postprandial blood glucose, insulin dosage, and insulin usage within the body. It is still contested which form of exercise/physical activity is best for pregnant women, yet some movement is better than no movement. Although exercise does not reduce the risk of developing GDM, it does help reduce some of the associated risks. When it comes to exercise in pregnant women who have GDM there is a decrease in the risk of having a newborn with macrosomia, decrease in maternal weight gain and a decrease in c-sections. Although exercise is not the cure for GDM, it does help pregnant women decrease any complications or risk factors that can arise from the disease. Self-monitoring can be accomplished using a handheld capillary glucose dosage system. Compliance with these glucometer systems can be low. There is not a lot of research into what target blood sugar levels should be for women with gestational diabetes, and targets recommended to women vary globally. Target ranges advised by the Australasian Diabetes in Pregnancy Society are as follows:
== Career == In early 1964, Sarkar presented his PhD research at the Federation of American Societies for Experimental Biology (FASEB) meeting in Chicago, where he was approached by Andrew Sass-Kortsak, a clinician specializing in Wilson's disease at Toronto's Hospital for Sick Children. Sass-Kortsak, then leading the hospital's Genetic Metabolic Program, sought a basic scientist to join his team and offered Sarkar a staff scientist position. This role included start-up funding and a dedicated laboratory in a newly constructed wing of the hospital. Shortly after, Sarkar received a cross-appointment to the University of Toronto's Department of Biochemistry. Sarkar began attending clinical Grand Rounds with Sass-Kortsak and visited Wilson's disease patients in hospital wards. His research shifted toward metal-related disorders, driven by his expertise in biophysical studies of metal-protein interactions and metal transport. Collaborating with Sass-Kortsak, Sarkar pioneered multidisciplinary research at SickKids, bridging basic science and clinical medicine to foster a collaborative institutional environment. In 1990, he was appointed head of the Division of Biochemistry Research at SickKids.
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.
Dry powder is best kept sealed, protected from light, and held at minus 20 degrees Celsius or below. Desiccant packaging helps limit moisture uptake because the material is hygroscopic. A sealed vial should be allowed to equilibrate to room temperature before opening to reduce condensation.