The short version of Intranasal route fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-05-10. Anything still debated is marked as such rather than presented as settled.
The compound was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences during the 1980s and 1990s. The stated design goal was to retain the immunomodulatory and central nervous system activity attributed to tuftsin while improving resistance to enzymatic breakdown. Adding a proline-rich tail to the short parent peptide was a deliberate strategy, because proline residues restrict the conformations available to many peptidases. The same laboratory produced Semax, an ACTH fragment analog, and both compounds were developed in parallel as short, enzymatically stabilized peptides intended for intranasal use.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Peptide sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Seven residues; tuftsin plus a Pro-Gly-Pro tail |
| Molecular formula | C33H57N11O9 | Commonly reported value for the free peptide |
| Monoisotopic mass | Roughly 751.4 Da | Average molecular mass near 751.9 Da |
| Appearance | White to off-white powder | Typically supplied as a lyophilized solid |
| Solubility class | Freely soluble in water | Also dissolves in saline and other polar solvents |
Peptide bonds in selank are susceptible to hydrolysis under strongly acidic or basic conditions, and the terminal proline residues are vulnerable to exopeptidase activity in biological samples. Lyophilized powder stored dry at -20 °C typically remains stable for extended periods, whereas aqueous solutions degrade faster and may lose measurable purity within days to weeks depending on pH, temperature, and microbial load. Repeated freeze-thaw cycles promote aggregation and adsorption to container surfaces. For analytical work, solutions are usually prepared fresh, kept cold, and used within a single working day.
Handling follows standard practice for research peptides. Material is weighed in a low-humidity environment because the powder absorbs atmospheric moisture. Purity is reported as the percentage area of the main peak in a chromatogram, with specifications commonly set at 95 percent or higher; values below that threshold indicate the presence of truncated or modified species. Residual trifluoroacetate from purification is often present and may affect mass balance. Certificates of analysis should state the analytical method, the column and gradient used, and the lot-specific retention time so that results can be compared across suppliers.
Identity and purity of selank are established with reversed-phase high-performance liquid chromatography coupled to mass spectrometry. The peptide elutes from C18 columns with acetonitrile gradients in water containing trifluoroacetic acid or formic acid, and detection is usually performed by ultraviolet absorbance near 214 nm. Electrospray ionization in positive mode gives a doubly protonated ion near m/z 377, consistent with a mass of about 752 Da. Amino acid analysis or tandem mass spectrometry of fragment ions confirms the sequence. Because the molecule has no aromatic residues, it lacks a usable 280 nm chromophore, so low-wavelength detection or mass spectrometry is required.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, frequently abbreviated as TKPRPGP. It was designed as a structural analogue of tuftsin, a naturally occurring tetrapeptide released by enzymatic cleavage of the immunoglobulin heavy chain. The two additional proline residues at the C-terminal end extend the parent chain and change how the molecule behaves in solution. The free peptide has a calculated molecular mass of approximately 751.9 g/mol and is generally supplied as a lyophilised white to off-white powder.
Development work on the compound began in the 1980s and 1990s at the Institute of Molecular Genetics in Moscow, within the same research programme that produced the peptide Semax. Early investigators sought a tuftsin derivative with improved resistance to enzymatic breakdown and with activity in the central nervous system after peripheral administration. Most of the primary literature from this period was published in Russian, a factor that still shapes how easily the findings can be checked by outside groups.
Naming for this compound is not fully standardised in English sources. The spelling Selanc appears in some transliterations, and catalogue entries may instead list the peptide sequence itself as the identifier. Reference material sometimes groups it with other short synthetic peptides studied for behavioural effects, which can create confusion when citations are compared. Distinguishing the exact sequence from related tuftsin analogues is therefore a practical first step when reviewing any dataset or specification sheet.
== Treatment == Standard intravenous preparations of potassium phosphate are available and are routinely used in malnourished people and people who consume excessive amounts of alcohol. Supplementation by mouth is also useful where no intravenous treatment are available. Historically one of the first demonstrations of this was in people in concentration camp who died soon after being re-fed: it was observed that those given milk (high in phosphate) had a higher survival rate than those who did not get milk. Monitoring parameters during correction with IV phosphate
==== Nations ==== India: Randhir Jaiswal, the official spokesperson of the Ministry of External Affairs, expressed strong condemnation of the strikes and expressed support for Afghanistan's sovereignty and territorial integrity. Qatar: Qatari foreign minister Mohammed bin Abdulaziz Al Khulaifi discussed with Pakistani Foreign Minister Muhammad Ishaq Dar ways to reduce tension between Pakistan and Afghanistan, thereby strengthening security and stability in the region. Russia: The Russian government offered to mediate the situation and urged both nations to halt cross-border attacks. Saudi Arabia: Prince Faisal bin Farhan and officials in the Pakistani government discussed ways to reduce regional tensions during a phone call. United States: The White House stated that it will continue to monitor the situation closely and expressed support for Pakistan against the Taliban attacks. US president Donald Trump praised both Shehbaz Sharif and Asim Munir for fighting against Taliban forces. In addition, Bangladesh, China, Egypt, Iran, Iraq, Jordan, Malaysia, and Uzbekistan also called for a ceasefire to end hostilities and promoted dialogue to resolve border tensions.
General statistics indicate that 70–80 percent of women require direct clitoral stimulation (consistent manual, oral, or other concentrated friction against the external parts of the clitoris) to reach orgasm. Indirect clitoral stimulation (for example, by means of vaginal penetration) may also be sufficient for female orgasm. The area near the entrance of the vagina (the lower third) contains nearly 90 percent of the vaginal nerve endings, and there are areas in the anterior vaginal wall and between the top junction of the labia minora and the urinary meatus that are especially sensitive, but intense sexual pleasure, including orgasm, solely from vaginal stimulation is occasional or otherwise absent because the vagina has significantly fewer nerve endings than the clitoris. The prominent debate over the quantity of vaginal nerve endings began with Alfred Kinsey. Although Sigmund Freud's theory that clitoral orgasms are a prepubertal or adolescent phenomenon and that vaginal (or G-spot) orgasms are something that only physically mature females experience had been criticized before, Kinsey was the first researcher to harshly criticize the theory. Through his observations of female masturbation and interviews with thousands of women, Kinsey found that most of the women he observed and surveyed could not have vaginal orgasms, a finding that was also supported by his knowledge of sex organ anatomy. Scholar Janice M.
Sources: en.wikipedia.org
=== Forked connectivity === HDMI has supported Consumer Electronics Control (CEC) commands since the first version. The CEC bus allows connecting multiple sources to a single display, and controlling any of these devices from any remote. DisplayPort 1.3 added the possibility of transmitting CEC commands over the AUX channel. On the other hand, DisplayPort supports connecting multiple displays to one DP port via the Multi-Stream Transport (MST) feature, allowing a single computer to have multiple displays. These differences reflects the origins the two standards, and the priorities of their authors. HDMI originates from consumer electronics companies, whereas DisplayPort is owned by VESA, which started as an organization for computer standards.
=== Next generation PEGylation === Chilkoti's research group has developed next-generation polyethylene glycol (PEG)-like conjugates that overcome the immunogenicity issues associated with traditional PEGylation. PEGylation—the attachment of polyethylene glycol (PEG) to biologics—is commonly used to increase their half-life or reduce their immunogenicity, but PEG has itself proven to be antigenic and can elicit a serious anaphylactic response. To overcome these limitations, he designed a new PEG-like stealth hyperbranched polymer that breaks up the long antigenic ethylene glycol sequence in PEG and presents them as much shorter side-chains along a polymer backbone. Peptides and proteins conjugated to this next-generation PEG-like polymer show even longer circulation than PEG conjugates, do not bind to pre-existing anti-PEG antibodies that most people have developed, and do not generate an immune response to this new polymer. He has demonstrated the utility of this technology with a peptide drug for type 2 diabetes, an enzyme drug used to treat gout and an aptamer drug.
Several state courts and officials, including the Colorado Supreme Court, a state Circuit Court in Illinois, and the Secretary of State of Maine, ruled that Trump was ineligible to hold office under Section 3 of the Fourteenth Amendment to the United States Constitution for his role in the January 6 Capitol attack, and thus attempted to disqualify him from appearing on the ballot. These attempts were unsuccessful. On March 4, 2024, the U.S. Supreme Court unanimously ruled in Trump v. Anderson that states cannot determine eligibility for a national election under Section 3. The Court held that only Congress has the authority to disqualify candidates, or to pass legislation that allows courts to do so.
The PLA Ground Force (PLAGF) is the largest of the PLA's five services with 960,000 active duty personnel, approximately half of the PLA's total manpower of around 2 million personnel. The PLAGF is organized into twelve active duty group armies sequentially numbered from the 71st Group Army to the 83rd Group Army which are distributed to each of the PRC's five theatre commands, receiving two to three group armies per command. In wartime, numerous PLAGF reserve and paramilitary units may be mobilized to augment these active group armies. The PLAGF reserve component comprises approximately 510,000 personnel divided into thirty infantry and twelve anti-aircraft artillery (AAA) divisions. The PLAGF is led by Commander Li Qiaoming and Political Commissar Chen Hui (general).
Sources: en.wikipedia.org
The sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, written TKPRPGP in one-letter code. It combines the tetrapeptide tuftsin with a carboxyl-terminal Pro-Gly-Pro extension. This full sequence identifies the molecule more precisely than the research name.
No peptide with this exact sequence has been identified as an endogenous substance. It is a laboratory-designed analog of tuftsin, a naturally occurring immunomodulatory tetrapeptide. The Pro-Gly-Pro extension has no known natural source.
Proline introduces conformational constraints that make a peptide less accessible to common peptidases. This is a standard stabilization strategy in peptide design. The added residues also increase the distance between the active tuftsin portion and typical cleavage sites.
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.