A practical reference on ACTH(4-10): what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-08-08. 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 a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Semax is a synthetic peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
| 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 |
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
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.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Substances found, according to the reports, are 1-Naphthol, naphthalene, Sevin, tarry residues, organochlorines, mercury, chromium, copper, nickel, lead, hexachlorethane, hexachlorobutadiene, pesticide HCH, volatile organic compounds and halo-organics. Many of these contaminants were also found in breast milk of women living near the area. Soil tests were conducted by Greenpeace in 1999. One sample (IT9012) from "sediment collected from drain under former Sevin plant" showed mercury levels to be at "20,000 and 6 million times" higher than expected levels. Organochlorine compounds at elevated levels were also present in groundwater collected from (sample IT9040) a 4.4 metres (14 ft) depth "bore-hole within the former UCIL site". This sample was obtained from a source posted with a warning sign which read "Water unfit for consumption". Chemicals that have been linked to various forms of cancer were also discovered, as well as trichloroethylene, known to impair foetal development, at 50 times above safety limits specified by the U.S. Environmental Protection Agency (EPA). In 2002, an inquiry by Fact-Finding Mission on Bhopal found a number of toxins, including mercury, lead, 1,3,5 trichlorobenzene, dichloromethane and chloroform, in nursing women's breast milk. A 2004 BBC Radio 5 broadcast reported the site is contaminated with toxic chemicals including hexachlorocyclohexane and mercury, held in open containers or loose on the ground.
The large range and marked variability between individuals is due to variation in factors including product matrix, ignition temperature, and inhalational dynamics (e.g., number, duration, and intervals of inhalations, breath hold time, depth and volume of inhalations, size of inhaled particles, deposition site in the lungs). THC is detectable within seconds with inhalation and peak levels of THC occur after 3 to 10 minutes. Smoking or inhaling THC results in greater blood levels of THC and its metabolites and a much faster onset of action than oral administration of THC. Inhalation of THC bypasses the first-pass metabolism that occurs with oral administration. The bioavailability of THC with inhalation is increased in heavy users. Transdermal administration of THC is limited by its extreme water insolubility. Efficient skin transport can only be obtained with permeation enhancement. Transdermal administration of THC, as with inhalation, avoids the first-pass metabolism that occurs with oral administration.
According to experts in the field, 70% of all chemical reactions could be done in microreactors; however, only 10-15% are economically justified. With the exception of some stereospecific reactions, particularly biotechnology, mastering these technologies does not represent a distinct competitive advantage. Most reactions can be carried out in standard multipurpose plants. Reaction-specific equipment, such as ozone or phosgene generators, is readily available. The installation is not generally a critical path on the overall project for developing an industrial-scale process of a new molecule. Whereas the overall demand for outsourced pharmaceutical fine chemicals is expected to increase moderately, the estimated annual growth rates for the above-mentioned niche technologies are much higher. Microreactors, and the SMB separation technology, are expected to grow at a rate of 50–100% per year. The total size of the accessible market typically does not exceed a few hundred tons per year at best.
== Adverse effects == Side effects are similar to those of buprenorphine and other opioids. In addition, naloxone can induce withdrawal symptoms in people who are chemically dependent on opioids. The most common side effects (in order of most to least common) of sublingual tablets include headaches, opioid withdrawal syndrome, pain, nausea, increased sweating, and difficulty sleeping. The most common side effects seen in film formulations are tongue pain, decreased sensation and redness in the mouth, headache, nausea, vomiting, excessive sweating, constipation, signs and symptoms of opioid withdrawal, sleeping difficulties, pain, and swelling of the extremities. Post-approval, the most frequently reported side effects of buprenorphine/naloxone in sublingual strip form (i.e. Suboxone strips) are peripheral edema, stomatitis, glossitis, blistering of the mouth, and mouth ulcers (mouth sores). Use of buprenorphine/naloxone may also increase the risk of developing certain dental problems (including tooth decay and tooth loss). Buprenorphine/naloxone has a milder side effect profile than methadone and limited respiratory effects, due to both agonist/antagonist effects. But buprenorphine/naloxone may be less safe than methadone in people with stable liver disease since it can elevate liver enzymes.
=== Chemistry === Protein hydrolysis is a useful route to the isolation of individual amino acids. Examples include cystine from hydrolysis of hair, tryptophan from casein, histidine from red blood cells, and arginine from gelatin.
Sources: en.wikipedia.org
=== U.S. News & World Report's Best High Schools === Since 2007, U.S. News & World Report has ranked high schools in PGCPS among the Best High Schools in America. High Point High School, Northwestern High School, and Eleanor Roosevelt High School have been recognized as Silver Medal Schools.
This text states that if "you don't get attracted, grasp, and commit to the notion 'my self', you'll have no doubt or uncertainty that what arises is just suffering arising, and what ceases is just suffering ceasing." Similarly, the Mahānidānasutta (DN 15) associates understanding dependent origination with abandoning various wrong views about a self, while failing to understand it is associated becoming entangled in these views. Another sutra, SĀ 297, states that dependent origination is "the Dharma Discourse on Great Emptiness", and then proceeds to refute numerous forms of "self-view" (ātmadṛṣṭi). SN 12:12 (parallel at SĀ 372) the Buddha is asked a series of questions about the self (who feels? who craves? etc.), the Buddha states that these questions are invalid, and instead teaches dependent origination. SĀ 80 also discusses an important meditative attainment called the emptiness concentration (śūnyatāsamādhi) which in this text is associated contemplating how phenomena arise due to conditions and are subject to cessation.
== Culture == Historically, mushrooms that resemble human body parts or rotting flesh (such as this one) hold cultural relevance. In European and Indigenous cultures these types of fungi were frequently associated with supernatural beliefs or omens. In the past Dead Man's Foot held significance in land-spirit and fertility myths in some regions.
as shown above for one decay. The solution can be found by the integration factor method, where the integrating factor is eλBt. This case is perhaps the most useful since it can derive both the one-decay equation (above) and the equation for multi-decay chains (below) more directly.
Sources: en.wikipedia.org
644 1787 L'intégration de quelques équations aux différences Partielles (Legendre transform) In Memoires présentés par divers Savants à la l'Académie des Sciences de l'Institut de France 1806 Nouvelle formula pour réduire en distances vraies les distances apparentes de la Lune au Soleil ou à une étoile (30–54) 1807 Analyse des triangles tracés sur la surface d'un sphéroide (130–161) Tome 10 Recherches sur diverses sortes d'intégrales défines (416–509) 1819 Méthode des moindres carrés pour trouver le milieu le plus probable entre les résultats de différentes observations (149–154), Mémoire sur l'attraction des ellipsoïdes homogènes (155–183) 1823 Recherches sur quelques objets d'Analyse indéterminée et particulièrement sur le théorème de Fermat (1–60) 1828 Mémoire sur la détermination des fonctions Y et Z que satisfont à l'équation 4(X^n-1) = (X-1)(Y^2+-nZ^2), n étant un nombre premier 4i-+1 (81–100) 1833 Réflexions sur différentes manières de démontrer la théorie des parallèles ou le théorème sur la somme des trois angles du triangle, avec 1 planche (367–412)
Kinetic resolution of a racemic mixture Biocatalyzed asymmetric synthesis In kinetic resolution of a racemic mixture, the presence of a chiral object (the enzyme) converts one of the stereoisomers of the reactant into its product at a greater reaction rate than for the other reactant stereoisomer. The stereochemical mixture has now been transformed into a mixture of two different compounds, making them separable by normal methodology.
Fenthion is a common pesticide that is used to kill insects such as flies and gnats. It was also found that kestrels are highly susceptible to secondary fenthion poisoning. When 14 kestrels were presented with live sparrows who had come into contact with a fenthion solution, all 14 died within 3 days after consuming the sparrows. Diphacinone is another common pesticide that is often used to kill rodents and is thought to be related to secondary poisoning in birds of prey. When kestrels were orally dosed with diphacinone, blood clotting rates significantly decreases. Kestrels were also found to be 20 to 30 times more sensitive to secondary poisoning from diphacinone than other birds like Northern bobwhite and mallard ducks. The species has been used to monitor metals (Cd, Sn, Pb, Cu, Al, Hg) and metalloids (As) in western North American drylands using feathers as a suitable tool to measure environmental pollution. American kestrels can also be significantly influenced by air contaminants. When exposed to common gaseous pollutants such as benzene, toluene, nitrogen dioxide, and sulfur dioxide, significant changes to the thyroid systems were observed. Higher levels of thyroid activity indicate that exposure to these gases leads to a loss of inhibition of thyroid glands in kestrels. However, there were no changes to immune function or food consumption.
== Design == The design of an RTG is simple by the standards of nuclear technology: the main component is a sturdy container of a radioactive material (the fuel). Thermocouples are placed in the walls of the container, with the outer end of each thermocouple connected to a heat sink. Radioactive decay of the fuel produces heat. It is the temperature difference between the fuel and the heat sink that allows the thermocouples to generate electricity. A thermocouple is a thermoelectric device that can convert thermal energy directly into electrical energy using the Seebeck effect. It is made of two kinds of metal or semiconductor material. If they are connected to each other in a closed loop and the two junctions are at different temperatures, an electric current will flow in the loop. Typically a large number of thermocouples are connected in series to generate a higher voltage. RTGs and fission reactors use very different nuclear reactions. Nuclear power reactors (including the miniaturized ones used in space) perform controlled nuclear fission in a chain reaction. The rate of the reaction can be controlled with neutron absorbing control rods, so power can be varied with demand or shut off (almost) entirely for maintenance. However, care is needed to avoid uncontrolled operation at dangerously high power levels, or even nuclear accident. Chain reactions do not occur in RTGs. Heat is produced through spontaneous radioactive decay at a non-adjustable and steadily decreasing rate that depends only on the amount of fuel isotope and its half-life.
Polyethyleneglycols are used in perfumes, cosmetics, pharmaceuticals, lubricants, paint thinners, and plasticizers. Ethylene glycol ethers are part of brake fluids, detergents, solvents, lacquers, and paints. Ethanolamines are used in the manufacture of soap and detergents and for purification of natural gas. Ethoxylates are reaction products of ethylene oxide with higher alcohols, acids, or amines. They are used in the manufacture of detergents, surfactants, emulsifiers, and dispersants. Whereas synthesis of ethylene glycols is the major application of ethylene oxide, its percentage varies greatly depending on the region: from 44% in the Western Europe, 63% in Japan, and 73% in North America to 90% in the rest of Asia, and 99% in Africa.
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.
Registered medical products are most often 0.1% nasal drops. Research suppliers ship lyophilized powder, usually in milligram quantities, which is dissolved before use. The active peptide is the same in both cases; presentation and excipients differ.