Everything below concerns GABA-A receptor. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-07-05. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Route studied | Intranasal | Predominant route in published reports |
| Circulation stability | Short, minutes scale | Peptidases cleave it; the tail slows the process |
| Analytical method | RP-HPLC with mass spectrometry | Used for identity and purity assessment |
| Reported outcome domains | Anxiety and cognitive measures | Derived from small, mostly regional trials |
| Regulatory status | Marketed in Russia | Availability outside that market is limited |
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.
Peptide stability depends strongly on temperature, moisture, and pH. Lyophilized Selank is generally most stable when stored cold and dry, with freezer temperatures commonly used for long-term storage. In solution, the compound is susceptible to hydrolysis and to microbial growth if it is not handled aseptically. The C-terminal proline-rich extension appears to slow enzymatic cleavage relative to tuftsin, though quantitative degradation rates vary with the matrix and the conditions tested. Published stability data specific to Selank remain sparse.
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.
==== The tandem principle ==== The solution emerged from a charge-reversal concept proposed demonstrated by Nobel laureate Luis Alvarez in 1951. Rather than accelerate positive ions from ground to a high-voltage terminal, the tandem accelerator begins with negative ions. These particles accelerate toward a positive terminal, where a thin foil or gas stripper removes multiple electrons, converting them to positive ions. The now-positive particles accelerate away from the terminal back to ground potential. This double acceleration effectively multiplies the particle energy without requiring proportionally higher terminal voltages. A negative hydrogen ion accelerated through a 5 megavolt tandem emerges with 10 megavolts of kinetic energy. After commissioning tandem production in 1954, Atomic Energy of Canada Limited placed HVEC's first tandem order in September 1956 for $0.92M (equivalent to $10.89M in 2025). The machine achieved first beam at HVEC's Burlington facility in June 1958.
To promote weight gain and muscle growth As an adjunct in the treatment of bone pain and decreased bone strength associated with osteoporosis As an adjunct for catabolic states such as corticosteroid therapy and convalescence as in chronic infections, extensive surgery, and severe trauma To treat treatment-refractory anemias (via stimulation of erythropoiesis) such as acquired and congenital aplastic anemia and anemia of chronic kidney disease As an adjunct to improve strength and well-being in arthritis To treat short stature in youth
==== Women's international friendly matches ==== 22 February – China 0–0 Ireland. 8 April – USA 2–0 Ireland. 11 April – USA 1–0 Ireland. 22 June – Ireland 3–2 Zambia. 6 July – Ireland 0–3 France. 14 July – A friendly pre-World Cup warmup match against Colombia in Brisbane was abandoned after 20 minutes following harsh incidents by the South Americans against Denise O'Sullivan and Ruesha Littlejohn which earned the offenders yellow cards. O'Sullivan went to hospital with an injury inflicted by Colombian Daniela Caracas who said after the match that the Irish players "are little girls" ("Son unas nenas"), and "let them eat shit" ("que coman mierda").
h = the reduced plate height count (plate height/stationary phase particle diameter) n = the reduced mobile phase linear velocity (velocity times stationary phase particle diameter/solute diffusion coefficient in the mobile phase) A, B, and C are constants related to solute flow anisotropy (eddy diffusion), molecular longitudinal diffusion, and mass transfer properties respectively. Berthod's use of the Knox equation to experimentally determine which of the proposed theories was most correct led him to the following conclusions. The flow anisotropy in micellar phase seems to be much greater than in traditional hydro-organic mobile phases of similar viscosity. This is likely due to the partial clogging of the stationary phase pores by adsorbed surfactant molecules. Raising the column temperature served to both decrease viscosity of the mobile phase and the amount of adsorbed surfactant. Both results reduce the A term and the amount of eddy diffusion, and thereby increase efficiency. The increase in the B term, as related to longitudinal diffusion, is associated with the decrease in the solute diffusion coefficient in the mobile phase, DM, due to the presence of the micelles, and an increase in the capacity factor, k¢. Again, this is related to surfactant adsorption on the stationary phase causing a dramatic decrease in the solute diffusion coefficient in the stationary phase, DS. Again an increase in temperature, now coupled with an addition of alcohol to the mobile phase, drastically decreases the amount of the absorbed surfactant.
Sources: en.wikipedia.org
== History == 3,4-DMA was first described in the scientific literature by Gordon Alles by 1932. Its effects in humans were first described by Mahlon David Fairchild by 1963. Subsequently, the drug was described in greater detail by Alexander Shulgin in his book PiHKAL (Phenethylamines I Have Known and Loved) in 1991.
Finally, they contend that remote administration may result in an increased risk that insufficient amounts of the lethal-injection drugs enter the inmate's bloodstream. In summary, opponents argue that the effect of dilution or of improper administration of thiopental is that the inmate dies an agonizing death through suffocation due to the paralytic effects of pancuronium bromide and the intense burning sensation caused by potassium chloride. Opponents of lethal injection, as practiced, argue that the procedure is designed to create the appearance of serenity and a painless death, rather than actually providing it. Specifically, opponents object to the use of pancuronium bromide, arguing that it serves no useful purpose in lethal injection since the inmate is physically restrained. Therefore, the default function of pancuronium bromide would be to suppress the autonomic nervous system, specifically to stop breathing.
== Lineage == Constituted 5 July 1942 in the Army of the United States as the 2d Company, 1st Battalion, First Regiment, 1st Special Service Force, a combined Canadian-American organization Activated on 9 July 1942 at Fort William Henry Harrison, Montana Disbanded on 6 January 1945 in France Reconstituted on 15 April 1960 in the Regular Army; concurrently consolidated with Company B, 1st Ranger Infantry Battalion (activated 19 June 1942), and consolidated unit redesignated as Headquarters and Headquarters Company, 1st Special Forces Group, 1st Special Forces Consolidated on 30 September 1960 with Headquarters and Headquarters Company, 1st Special Forces Group (constituted 14 June 1957 in the Regular Army and activated 24 June 1957 in Japan), and the consolidated unit was designated as Headquarters and Headquarters Company, 1st Special Forces Group, 1st Special Forces (organic units concurrently constituted and activated 4 October 1960) Group inactivated 30 June 1974 at Fort Bragg, North Carolina Activated 1 September 1984 at Fort Lewis, Washington (Former Company B, 1st Ranger Infantry Battalion, withdrawn 3 February 1986, consolidated with Company N, 75th Infantry, and consolidated unit redesignated as Company N, 75th Ranger Regiment – hereafter separate lineage) Redesignated 1 October 2005 as the 1st Special Forces Group, 1st Special Forces Regiment
Serous acinar cells are roughly pyramid shape, with the apex of the pyramid pointing towards to the center of the (roughly spherical) acinus. Inside of the cell on the side with the apex, there are specialize saliva-material containing structures called secretory granules. Compared to mucous acinar cells, their nuclei is more round, and centrally located.
Topical nonsteroidal anti-inflammatory drugs provide pain relief in common conditions such as muscle sprains and overuse injuries. Since the side effects are also lesser, topical preparations could be preferred over oral medications in these conditions. Some novel and investigational analgesics include subtype-selective voltage-gated sodium channel blockers such as funapide and raxatrigine, as well as multimodal agents such as ralfinamide. Audioanalgesia Electroanalgesia Pain management Patient-controlled analgesia Pain in babies Congenital analgesia (insensitivity to pain)
Sources: en.wikipedia.org
The calculations given above produce dates in radiocarbon years: i.e. dates that represent the age the sample would be if the 14C/12C ratio had been constant historically. Although Libby had pointed out as early as 1955 the possibility that this assumption was incorrect, it was not until discrepancies began to accumulate between measured ages and known historical dates for artefacts that it became clear that a correction would need to be applied to radiocarbon ages to obtain calendar dates. To produce a curve that can be used to relate calendar years to radiocarbon years, a sequence of securely dated samples is needed which can be tested to determine their radiocarbon age. The study of tree rings led to the first such sequence: individual pieces of wood show characteristic sequences of rings that vary in thickness because of environmental factors such as the amount of rainfall in a given year. These factors affect all trees in an area, so examining tree-ring sequences from old wood allows the identification of overlapping sequences. In this way, an uninterrupted sequence of tree rings can be extended far into the past. The first such published sequence, based on bristlecone pine tree rings, was created by Wesley Ferguson. Hans Suess used this data to publish the first calibration curve for radiocarbon dating in 1967. The curve showed two types of variation from the straight line: a long term fluctuation with a period of about 9,000 years, and a shorter-term variation, often referred to as "wiggles", with a period of decades.
== Neurodegeneration == Inhibition of Hsp90 leads to Hsp70 and Hsp40 upregulation, which can channel misfolded protein for proteasome degradation, which can potentially inhibit the progression of neurodegenerative diseases. For example, Hsp70 overexpression in human neuroglioma cells transfected with mutant alpha-synuclein led to 50% less oligomeric alpha-synuclein species, pointing towards the possibility that increasing its expression could diminish the spread of Parkinson's disease. Similarly, Hsp70 overexpression suppressed poly-Q dependent aggregation and neurodegeneration in cell cultures, yeast, fly, and mouse models, and deletion of hsp70 increased the size of polyQ inclusion bodies, suggesting that increasing its expression could help to prevent Huntington's disease. Similarly, reductions in Hsp70 have been shown in transgenic mouse models of ALS and patients with sporadic ALS. Lastly, increased expression or activity of Hsp70 has been proposed as a method to prevent the progression of Alzheimer's disease, because knock down of Hsp70 promoted A-beta toxicity, and Hsp70 was shown to promote tau stability, while Hsp70 levels are decreased in tauopathies like Alzheimer's disease. Given the complex interplay between the different chaperone proteins, therapeutic development in this field is aimed at investigating how the chaperone network as a whole can be manipulated and the effect of this manipulation on the progression of neurodegenerative disease, but the balance of Hsp70 and Hsp90 levels appears to be central in this pathophysiology.
=== Surgery === Corneal transplant surgery may be difficult due to the peripheral thinning of the cornea, even with large and off-center grafts. Therefore, surgery is usually reserved for people that do not tolerate contact lenses. Several different surgical approaches may be taken, and no one approach is currently established as the standard. Examples of surgical procedures used for PMD include: wedge resection, lamellar crescentic resection, penetrating keratoplasty, lamellar keratoplasty, epikeratoplasty and intracorneal segments. Transplantation of the entire thickness of the cornea (penetrating keratoplasty) may be performed if there is enough normal tissue present. However, if there is not enough normal tissue present, then attaching the graft is difficult. New surgical techniques are in evaluation such as Intrastromal lamellar Keratoplasties and Sclerocorneal Intrastromal Lamellar Keratoplasty (SILK), these techniques allow thickening of the inferior peripheral cornea and steepening of the vertical meridien. Due to the thinning of the cornea, people with PMD are poor candidates for procedures such as LASIK and photorefractive keratectomy.
So far, four species from the genus Pediococcus have been isolated in wines and grape must, P. inopinatus, P. pentosaceus, P. parvulus, and P. damnosus, with the last two being the species most commonly found in wine. All Pediococcus species are Gram-positive with some species being micro-aerophilic while others utilizing mostly aerobic respiration. Under the microscope, Pediococcus often appear in pairs of pairs or tetrads which can make them identifiable. Pediococci are homofermenters, metabolizing glucose into a racemic mixture of both L- and D-lactate by glycolysis. However, in the absence of glucose, some species, such as P. pentosaceus, begin using glycerol, degrading it into pyruvate which later can be converted to diacetyl, acetate, 2,3-butanediol and other compounds that can impart unfavorable characteristics to the wine. Most Pediococcus species are undesirable in winemaking due to the high levels of diacetyl that can be produced, as well as increased production of biogenic amines that has been implicated as one potential cause for red wine headaches. Many species of Pediococcus also have the potential to introduce off odors or other wine faults to the wine such as the bitter-tasting "acrolein taint" that comes from degradation of glycerol into acrolein which then reacts with phenolic compounds in the wine to produce a bitter-tasting compound. One species, P.
Sources: en.wikipedia.org
Reports describe effects on GABA-A receptor expression, monoamine turnover, and neurotrophic factor levels. These are proposed mechanisms drawn mainly from animal models. No single molecular target has been established.
Intranasal delivery is the route described in most published work. It is used because the peptide is degraded quickly once it reaches circulation. Direct evidence of brain penetration in humans is lacking.
Most trials are small, regionally concentrated, and often lack rigorous blinding or placebo control. Independent replication is limited. Reviews in English generally rate the evidence as preliminary.
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.