This is a working overview of Pro-Gly-Pro tail, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-02-05. Anything still debated is marked as such rather than presented as settled.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Semax is supplied as a lyophilized powder that appears white to off-white. It dissolves readily in water, phosphate-buffered saline, and other aqueous media, which simplifies preparation of working solutions for laboratory use. The nasal products registered in Russia are dilute aqueous solutions, typically around 0.1 percent peptide by weight. Organic solvents are rarely necessary and can complicate handling. Because the peptide is hygroscopic, weighing should be performed quickly and with minimal exposure to ambient humidity.
Solid material is normally kept at minus 20 degrees Celsius in a sealed, desiccated container. Reconstituted solutions are less stable and are usually divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of activity. Light exposure is minimized by using amber glassware or foil wrapping. Published stability data for this peptide are sparse, so recommended storage conditions rest mainly on general practice for short synthetic peptides rather than on dedicated study.
Identity and purity are commonly assessed by reversed-phase high-performance liquid chromatography, with ultraviolet detection near 214 nanometers for the peptide backbone. Mass spectrometry, either electrospray or matrix-assisted laser desorption, confirms molecular mass and detects truncation or modification products. Amino acid analysis can verify composition. Because the sequence contains no strongly absorbing aromatic residue apart from phenylalanine, detection wavelengths are chosen carefully. Purity values above 95 percent are typical for research-grade material.
| Property | Value | Notes |
|---|---|---|
| Molecular weight | ~813.9 Da (free heptapeptide) | N-acetylated form is about 42 Da heavier |
| Residue count | 7 (heptapeptide) | Four residues from ACTH(4-10), three added |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility class | Freely soluble in water | Also dissolves in DMSO and polar organic solvents |
| Related parent fragment | ACTH(4-10) | Parent motif is Met-Glu-His-Phe |
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Published research has focused mainly on neurological and cognitive endpoints in animal models, with proposed mechanisms involving brain-derived neurotrophic factor and related signalling pathways. A substantial share of the human data originates from a limited number of research groups, and independent replication in other countries remains sparse. Regulatory status reflects that distribution: the peptide is registered as a medicine in Russia and appears in some neighbouring markets, while elsewhere it is handled as a research chemical without approved therapeutic labelling. Questions about dose-response relationships, long-term effects, and comparability across studies are still open.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
== Production == The series is a Movistar Plus+ original, produced in collaboration with Suma Content. Shooting locations in Catalonia included Barcelona, Girona, Mataró, Òrrius, Santa Eulàlia de Ronçana, Calaf, Arenys de Mar, Manresa, Gualba, and Santa Susanna. The series was lensed by Gris Jordana. Raül Refree (score) and Hidrogenesse (original songs) were responsible for the music.
== Causes == The underlying cause of the rapidly growing breast connective tissue, resulting in gigantic proportions, has not been well elucidated. However, proposed factors have included increased levels/expression of or heightened sensitivity to certain hormones (e.g., estrogen, progesterone, and prolactin) and/or growth factors (e.g., hepatocyte growth factor, insulin-like growth factor 1, and epidermal growth factor) in the breasts. Macromastic breasts are reported to be composed mainly of adipose and fibrous tissue, while glandular tissue remains essentially stable. Macromastia occurs in approximately half of women with aromatase excess syndrome (a condition of hyperestrogenism). Hyperprolactinaemia has been reported as a cause of some cases of macromastia. Macromastia has also been associated with hypercalcaemia (which is thought to be due to excessive production of parathyroid hormone-related protein) and, rarely, systemic lupus erythematosus and pseudoangiomatous stromal hyperplasia. It is also notable that approximately two-thirds of women with macromastia are obese. Aside from aromatase (as in aromatase excess syndrome), at least two other genetic mutations (one in PTEN, the other "MDNS" not yet located to gene level) have been implicated in causing macromastia. A handful of drugs have been associated with gigantomastia, including penicillamine, bucillamine, neothetazone, ciclosporin, indinavir, and prednisolone.
An electronic cigarette (e-cigarette) or vape is a device that simulates tobacco smoking. It consists of an atomizer, a power source such as a battery, and a container such as a cartridge or tank. Instead of smoke, the user inhales vapor, often called "vaping". The atomizer is a heating element that vaporizes a liquid solution called e-liquid that cools into an aerosol of tiny droplets, vapor and air. The vapor mainly comprises propylene glycol or glycerin, usually with nicotine and flavoring. Its exact composition varies, and depends on matters such as user behavior. E-cigarettes are activated by taking a puff or pressing a button. Some look like traditional cigarettes, and most kinds are reusable. Vaping is less harmful than smoking, but still has health risks, particularly for those with asthma. Limited evidence indicates that e-cigarettes are less addictive than smoking, with slower nicotine absorption rates. E-cigarettes containing nicotine are more effective than nicotine replacement therapy (NRT) for smoking cessation, but have not been tested as rigorously as nicotine replacement therapy products.
=== Role in protein structure and function === Aromatic amino acids stabilize folded structures of many proteins. Aromatic residues are found predominantly sequestered within the cores of globular proteins, although often comprise key portions of protein-protein or protein-ligand interaction interfaces on the protein surface.
This was a controversial measure in Labour strongholds such as East London, Merseyside and North East England. He obtained a Treasury grant of £77 million to build the Docklands Light Railway, although transport links to Docklands remained inadequate. He opened Britain's first Enterprise Zone at Corby in Northamptonshire. Some criticism was made of his time in Liverpool that he spent a lot of money but generated little in the way of new employment ("I would not blame him for that: Liverpool had defeated better men than Michael Heseltine" commented Lady Thatcher acidly in her memoirs in 1993). Local Labour politicians tended to feel that he had accomplished little, although they acknowledged his good intentions. However a more positive assessment was offered by Michael Parkinson, Professor of Urban Affairs at John Moores University: although he had been sceptical in the 1980s, by 1997 he had come to favour the policies championed by Heseltine: assignment of ministers to regions, development of housing associations and cooperatives, and the channelling of government money through business-led agencies rather than through local government.
Sources: en.wikipedia.org
=== Symptoms of exposure === β-Amanitin may cause irritation of the respiratory tract, headache, dizziness, nausea, shortness of breath, coughing, insomnia, diarrhea, gastrointestinal disturbances, back pain, urinary frequency, liver and kidney damage, or death if ingested or inhaled. If β-Amanitin comes in contact with skin, it may cause irritation, burns, redness, severe pain, and could be absorbed through the skin, causing similar effects to exposure via inhalation and ingestion. Contact with the eyes may result in irritation, corneal burns, and eye damage. Persons with pre-existing skin, eye, or central nervous systems disorders, impaired liver, kidney, or pulmonary function may be more susceptible to the effects of this substance.
== Structure == There are about 1 million islets distributed throughout the pancreas of a healthy adult human. While islets vary in size, the average diameter is about 0.2 mm.:928 Each islet is separated from the surrounding pancreatic tissue by a thin, fibrous, connective tissue capsule which is continuous with the fibrous connective tissue that is interwoven throughout the rest of the pancreas.:928
=== Transorbital lobotomy === The Freeman-Watts prefrontal lobotomy still required drilling holes in the skull, so surgery had to be performed in an operating room by trained neurosurgeons. Walter Freeman believed this surgery would be unavailable to those he saw as needing it most: patients in state mental hospitals that had no operating rooms, surgeons, or anesthesia, and limited budgets. Freeman wanted to simplify the procedure so that psychiatrists could carry it out in psychiatric hospitals. Inspired by the work of Italian psychiatrist Amarro Fiamberti, Freeman at some point conceived of approaching the frontal lobes through the eye sockets instead of through drilled holes in the skull. In 1945, he took an ice pick from his own kitchen and began testing the idea on grapefruit and cadavers. The use of lobotomy in the United States was resisted and criticized heavily by American neurosurgeons. However, because Freeman managed to promote the success of the surgery through the media, lobotomy became touted as a miracle procedure, capturing the attention of the public and leading to an overwhelming demand for the operation. In 1945, Freeman streamlined the procedure, replacing it with transorbital lobotomy, in which a pick-like instrument was forced through the back of the eye sockets to pierce the thin bone that separates the eye sockets from the frontal lobes. The pick's point was then inserted into the frontal lobe and used to sever connections in the brain (presumably between the prefrontal cortex and thalamus).
== External links == "Relaxin Family Peptide Receptors: RXFP4". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical Pharmacology. Archived from the original on 2016-03-03. Retrieved 2008-12-09.
Sources: en.wikipedia.org
This money was used for improvements and security enhancements at research and storage facilities. Safety of nuclear facilities in Russia has been significantly improved since the stabilization of political and economical turmoil of the early 1990s. For example, in 1993 there were 29 incidents ranking above level 1 on the International Nuclear Event Scale, and this number dropped under four per year in 1995–2003. The number of employees receiving annual radiation doses above 20 mSv, which is equivalent to a single full-body CT scan, saw a strong decline around 2000. In November 2015, the Russian government approved a federal program for nuclear and radiation safety for 2016 to 2030 with a budget of 562 billion rubles (ca. 8 billion USD). Its key issue is "the deferred liabilities accumulated during the 70 years of the nuclear industry, particularly during the time of the Soviet Union". About 73% of the budget will be spent on decommissioning aged and obsolete nuclear reactors and nuclear facilities, especially those involved in state defense programs; 20% will go in processing and disposal of nuclear fuel and radioactive waste, and 5% into monitoring and ensuring of nuclear and radiation safety.
== Structure == Somatotropic cells constitute about 30−40% of anterior pituitary cells. They release growth hormone (GH) in response to growth hormone releasing hormone (GHRH, or somatocrinin) or are inhibited by GHIH (somatostatin), both received from the hypothalamus via the hypophyseal portal system vein and the secondary plexus.
11 January 1919: The Germans recapture Sarnowa and win in Battle of Zbąszyń; Polish victory in Battle of Szubin and capture Łabiszyn, Złotniki and Żnin. 12 January 1919: fighting near Leszno and Lipno. 13 January 1919: The Germans recapture Szamocin. 14 January 1919: The Commission of the NRL appeals to Roman Dmowski for help negotiate a ceasefire. 15 January 1919: failed attempt to recapture Szamocin by Poles. 16 January 1919 The first number of Tygodnik Urzędowy Naczelnej Rady Ludowej, with the laws of the NRL, is published. The Polish government of Ignacy Paderewski has two politicians of Greater Poland: Józef Englich, the minister of treasury, and Kazimierz Hącia, the minister of industry and trade. 17 January 1919: Men born in 1897, 1898, and 1899 are called up and drafted into Great Polish Army. 20 January 1919: the transfer of money to banks of Germany on the other side of the front line is forbidden. 21 January 1919 NRL creates oath of soldiers of Great Polish Army. 22 January 1919 Northern front: Poles are forced to leave Potulice. Southern front: Poles win the Battle of Robaczysko. Joseph Noulens is nominated by Supreme Council of Allied Countries as chief of Allied mission in Poland. 23 January 1919: Poles defend Miejska Górka after heavy fighting. 25 January 1919 Poles capture Babimost and Kargowa. All communication between Greater Poland and Germany is broken. Decree cancels Prussian prohibition of Polish language in schools.
It controls or suppresses broadleaf weeds, grasses and sedges and is effective on a very wide range of species including Abutilon theophrasti, Acalypha ostryifolia, Acanthospermum hispidum, Amaranthus palmeri, Ambrosia artemisiifolia, Anoda cristata, Barbarea vulgaris, Brassica kaber, Calystegia sepium, Cannabis sativa, Cardiospermum halicacabum, Cassia obtusifolia, Chenopodium album, Citrullus lanatus, Convolvulus arvensis, Croton glandulosus, Cyperus esculentus, Datura stramonium, Digitaria, Echinochloa crus-galli, Eleusine indica, Euphorbia heterophylla, Helianthus annuus, Hibiscus trionum, Ipomoea quamoclit, Melochia corchorifolia, Mollugo verticillata, Polygonum convolvulus, Portulaca oleracea, Richardia scabra, Sesbania exaltata, Setaria faberi, Solanum rostratum, Sorghum halepense, Striga asiatica and Xanthium strumarium. The product is typically used at application rates of 0.375 lb a.i. per acre. The estimated annual use of acifluorfen in US agriculture is mapped by the US Geological Service and shows that as of 2018 approximately 550,000 pounds (250,000 kg) were applied — mainly in soybean. The compound is not registered for use in the European Union, although a closely related nitrophenyl ether, bifenox, is available there.
NAD and its precursors nicotinic acid (NA) and nicotinamide (NAM) have been shown to be vital cofactors in cellular oxidation/reduction reactions and ATP synthesis. Classic NAD synthesis pathways characterized in eukaryotes include an eight-step de novo pathway from Trp and two pathways using the NAD precursors NA and NAM: a three-step NA-based pathway known as the Preiss-Handler pathway; and an NAM-based pathway involving the enzyme Nicotinamide phosphoribosyltransferase (NAMPT) and the formation of nicotinamide mononucleotide (NMN). In 2004, a previously unknown pathway was reported when nicotinamide riboside (NR) was identified as an additional NAD precursor in eukaryotes. NR is now recognized as a form of vitamin B3 which can be found in both cow and human milk. Once internalized into a cell, NR is rapidly phosphorylated by the activity of nicotinamide riboside kinase enzymes (NRK1 and NRK2) to form nicotinamide mononucleotide (NMN), bypassing the previously known biosynthetic routes to NAD production. NMN is then converted to NAD by NMN-adenylyltransferase (NMNAT). Research in mammals indicates that NRK1 is a cytosolic protein, encoded by the Nmrk1 gene. It is found in most tissues but predominantly in the liver and kidney. The NRK2 protein may be related to muscle tissue including cardiac muscle. It is encoded by the Nmrk2 gene and appears to be more highly expressed in cases of metabolic stress or cellular damage. Since different types of tissues display differing concentrations of NR and NRKs, it is likely that NR utilization will vary in different tissues.
Sources: en.wikipedia.org
The sequence is Met-Glu-His-Phe-Pro-Gly-Pro, a seven-residue peptide. The first four residues correspond to the ACTH(4-10) fragment, and Pro-Gly-Pro is added at the C-terminus. N-acetylated versions also appear in the literature and differ in mass.
Semax is a synthetic analog of the ACTH(4-10) fragment rather than a copy of the full hormone. Truncation plus the added tail removes the steroidogenic portion of ACTH. That distinction explains why it is studied for nervous-system effects instead of adrenal stimulation.
It is registered as a prescription product in Russia and has been used there clinically, chiefly by the intranasal route. No approval exists in the United States or the European Union. Availability elsewhere typically falls under research-chemical distribution, with varying purity documentation.
Solid peptide is best kept frozen at about minus 20 degrees Celsius in a sealed container with desiccant. It should be allowed to reach room temperature before opening to prevent condensation. Repeated warming and cooling of the same vial is discouraged.