This is a working overview of GABA-A receptor, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-06-09. Anything still debated is marked as such rather than presented as settled.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Modeled on tuftsin |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Seven residues |
| Approximate molecular mass | Around 750 Da | Depends on counter-ion and hydration |
| Common forms | Lyophilized powder | Also described as aqueous solution |
| Primary origin of research | Russian laboratories | Mid-1990s onward |
Pharmacokinetic data are sparse and largely derived from animal work. After intranasal administration the peptide appears in plasma within minutes, and reported half-lives are short, on the order of minutes to tens of minutes. Degradation proceeds through ordinary proteolytic cleavage into constituent amino acids and smaller fragments. Direct evidence that intact Selank reaches brain tissue in meaningful amounts is limited, and the extent of blood-brain barrier penetration is debated. Some authors argue that fragments, not the parent peptide, carry much of the observed activity.
Published clinical work is concentrated in Russian-language journals and generally involves small samples without independent replication. Systematic reviews in English note the shortage of randomised, placebo-controlled trials and the difficulty of verifying methods from translated reports. Outcome measures vary between studies, which complicates pooling of results. Interest in the compound as a cognitive or anxiolytic agent therefore rests on a thinner evidence base than the volume of citations suggests. Replication in well-powered trials with preregistered endpoints would be needed before firm conclusions about efficacy can be drawn.
Proposed mechanisms centre on the GABAergic system. Animal and tissue studies report changes in GABA-A receptor expression and reduced activity of GABA transaminase, the enzyme that degrades GABA. Effects on monoamine turnover, including serotonin and dopamine pathways, are also described, and a separate line of work links the peptide to increased expression of brain-derived neurotrophic factor in hippocampal tissue. Most of these findings come from rodent models and cell preparations. How the individual observations combine into a single coherent mode of action is not settled.
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.
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.
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.
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.
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.
The circulatory system consists of the heart and blood vessels (arteries, veins and capillaries). The heart propels the circulation of the blood, which serves as a "transportation system" to transfer oxygen, fuel, nutrients, waste products, immune cells and signaling molecules (i.e. hormones) from one part of the body to another. Paths of blood circulation within the human body can be divided into two circuits: the pulmonary circuit, which pumps blood to the lungs to receive oxygen and leave carbon dioxide, and the systemic circuit, which carries blood from the heart off to the rest of the body. The blood consists of fluid that carries cells in the circulation, including some that move from tissue to blood vessels and back, as well as the spleen and bone marrow.
Furthermore, problems with producing or using glutamate have been suggestively and tentatively linked to many mental disorders, including autism, obsessive–compulsive disorder (OCD), schizophrenia, and depression. Having too much glutamate has been linked to neurological diseases such as Parkinson's disease, multiple sclerosis, Alzheimer's disease, stroke, and ALS (amyotrophic lateral sclerosis).
Because of imperial expansion, immigration, and trading, ingredients and cooking techniques from other cultures have been integrated into Chinese cuisines over time and Chinese culinary influences have spread worldwide. There are numerous regional, religious, and ethnic styles of Chinese cuisine found within China and abroad. Chinese cuisine is highly diverse and most frequently categorised into provincial divisions, although these province-level classifications consist of many more styles within themselves. During the Qing dynasty, the most praised Four Great Traditions in Chinese cuisine were Chuan, Lu, Yue, and Huaiyang, representing cuisines of West, North, South, and East China, respectively. For example, in Northern China, the dry, temperate climate makes it suitable for the cultivation of wheat, millet and other grains. As such, noodles, porridge and bread are dietary staples. In 1980, a modern grouping from Chinese journalist Wang Shaoquan's article published in the People's Daily newspaper identified the Eight Cuisines of China as Anhui (徽菜; Huīcài), Guangdong (粵菜; Yuècài), Fujian (閩菜; Mǐncài), Hunan (湘菜; Xiāngcài), Jiangsu (蘇菜; Sūcài), Shandong (魯菜; Lǔcài), Sichuan (川菜; Chuāncài), and Zhejiang (浙菜; Zhècài).
== Education == Sereti received a M.D. from the University of Athens in 1991. She did research for one year in Gregory Spear's laboratory at Rush University Medical Center. Sereti completed an internship, residency, and chief residency in medicine at Northwestern University.
These enzymes cleave the β-lactam ring, an essential component of β-lactam antibiotics that are recognized by and bound to PBPs. Carbapenemases are divided into different classes, depending on the structure of the enzyme and the mechanism by which they hydrolyze the β-lactam ring. The two broad categories of carbapenemases are serine-carbapenemases, which contain serine at the active site, and metallocarbapenemases, which contain zinc at the active site. Class A carbapenemases are serine carbapenemases and are encoded on either the chromosome of the bacteria or a plasmid. A serine at position 70 at the active site of this class of enzymes is required for hydrolysis of β-lactams to occur. Class D carbapenemases, also referred to as the OXA β-lactamases, are serine β-lactamases. They are encoded on plasmids and contain a large variability in amino acid sequence. The resistance mechanism for class D carbapenemases is caused by the formation of an acyl intermediate when breaking the β-lactam ring. Class B carbapenemases are metallolactamases and require a zinc at the active site for hydrolysis. A clinical isolate of E. coli from the sputum sample of a patient admitted to a Beijing hospital was found to acquire resistance to carbapenem through mutations not previously observed. It involved a mutation of a regulator gene marR and the expression of a normally nontranslated membrane porin yedS; both mutations were demonstrated to have effects on the ability of this strain of E.coli to resist carbapenems.
Sources: en.wikipedia.org
Raleigh is the home of Raleigh Kubb, both a competitive and non-competitive kubb club. Raleigh Kubb hosts kubb tournaments benefitting various charities in the Raleigh area. The Raleigh Parks and Recreation Department offers a wide variety of leisure opportunities at more than 200 sites throughout the city, which include: 8,100 acres (33 km2) of park land, 78 mi (126 km) of greenway, 22 community centers, a BMX championship-caliber race track, 112 tennis courts among 25 locations, 5 public lakes, and 8 public aquatic facilities. The park system includes the historic Pullen Park, the oldest public park in North Carolina. The J. C. Raulston Arboretum, an 8-acre (32,000 m2) arboretum and botanical garden in west Raleigh administered by North Carolina State University, maintains a year-round collection that is open daily to the public without charge.
Gelsolin is an actin-binding protein that is a key regulator of actin filament assembly and disassembly. Gelsolin is one of the most potent members of the actin-severing gelsolin/villin superfamily, as it severs with nearly 100% efficiency. Cellular gelsolin, found within the cytosol and mitochondria, has a closely related secreted form, plasma gelsolin, that contains an additional 24 AA N-terminal extension. Plasma gelsolin's ability to sever actin filaments helps the body recover from disease and injury that leaks cellular actin into the blood. Additionally it plays important roles in host innate immunity, activating macrophages and localizing of inflammation.
=== United States === According to the US Food and Drug Administration (FDA), an orphan drug is defined as one "intended for the treatment, prevention or diagnosis of a rare disease or condition, which is one that affects less than 200,000 persons in the US" (which equates to approximately 6 cases per 10,000 population) "or meets cost recovery provisions of the act".
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Sources: en.wikipedia.org
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.
It originates from research in Russia, associated with the Institute of Molecular Genetics of the Russian Academy of Sciences. The first descriptions date to the mid-1990s. Most published studies come from Russian laboratories.
No, Selank itself does not occur naturally. Its backbone is based on tuftsin, which is produced in the body, but the seven-residue version is a synthetic construct. It is supplied as a manufactured peptide.
It is a seven-amino-acid peptide, Thr-Lys-Pro-Arg-Pro-Gly-Pro, produced by chemical synthesis rather than extracted from biological tissue. Its design is based on tuftsin, a natural immunomodulatory tetrapeptide. The C-terminal Pro-Gly-Pro segment is a common stabilising motif in short regulatory peptides.