Melanocortin receptor is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-06-21. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
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.
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
The heart has four valves, which separate its chambers. One valve lies between each atrium and ventricle, and one valve rests at the exit of each ventricle. The valves between the atria and ventricles are called the atrioventricular valves. Between the right atrium and the right ventricle is the tricuspid valve. The tricuspid valve has three cusps, which connect to chordae tendinae and three papillary muscles named the anterior, posterior, and septal muscles, after their relative positions. The mitral valve lies between the left atrium and left ventricle. It is also known as the bicuspid valve due to its having two cusps, an anterior and a posterior cusp. These cusps are also attached via chordae tendinae to two papillary muscles projecting from the ventricular wall. The papillary muscles extend from the walls of the heart to valves by cartilaginous connections called chordae tendinae. These muscles prevent the valves from falling too far back when they close. During the relaxation phase of the cardiac cycle, the papillary muscles are also relaxed and the tension on the chordae tendineae is slight. As the heart chambers contract, so do the papillary muscles. This creates tension on the chordae tendineae, helping to hold the cusps of the atrioventricular valves in place and preventing them from being blown back into the atria. Two additional semilunar valves sit at the exit of each of the ventricles. The pulmonary valve is located at the base of the pulmonary artery. This has three cusps which are not attached to any papillary muscles.
== Chemistry == On-line catalytic reduction of carbon monoxide to methane for detection by FID was described by Porter & Volman, who suggested that both carbon dioxide and carbon monoxide could also be converted to methane with the same nickel catalyst. This was confirmed by Johns & Thompson, who determined optimum operating parameters for each of the gases. CO2 + 2H2 ↔ CH4 + O2 2CO + 4H2 ↔ 2CH4 + O2
== Early career == After graduating from MIT, Swanson took a job at Citibank, where he managed a venture investment group. His performance pleased his supervisors, and he and a colleague were chosen to open a San Francisco office for Citicorp Venture Capital. However, the new Citicorp investments were not doing well. One particular failure, which Swanson later believed to have been a lucky break, was the bankruptcy of Antex, a science based company that Citicorp had invested in. He worked with Eugene Kleiner, another Citicorp executive, to attempt to get some money out of the company's bankruptcy. Eugene Kleiner was the cofounder of the venture capital partnership Kleiner & Perkins. Swanson left Citicorp and joined Kleiner & Perkins in 1974, under the recommendation of Eugene Kleiner himself. As an associate, Swanson spent a lot of time and effort attempting to convince the heads of the science company Cetus, one which Kleiner and Perkins had invested in, to pursue genetic recombination projects. His interest in the technology had been piqued in a lunch with famed scientist and Nobel laureate Donald Glaser. However, the company refused to take on such a risky endeavor, and Kleiner & Perkins parted ways with the company. This falling out was one of the main reasons for the group's decision to advise Swanson to look for another job. Kleiner & Perkins had decided that they would rather work alone, and by the end of 1975, Swanson's position there would be terminated.
Swiss chemist Albert Hofmann first synthesized LSD in 1938 and discovered its potent psychedelic effects in 1943 after accidental ingestion. It became widely studied in the 1950s and 1960s. The drug was initially explored for psychiatric use due to its structural similarity to serotonin and safety profile. It was used experimentally in psychiatry for treating alcoholism and schizophrenia. By the mid-1960s, LSD became central to the youth counterculture in places like San Francisco and London, influencing art, music, and social movements through events like Acid Tests and figures such as Timothy Leary, Owsley Stanley and Michael Hollingshead. Its psychedelic effects inspired distinct visual art styles and musical innovations, and caused a lasting cultural impact. However, its association with the counterculture movement of the 1960s led to its classification as a Schedule I drug in the United States in 1970. It was also listed as a Schedule I controlled substance by the United Nations in 1971 and remains without approved medical uses. Despite its legal restrictions, LSD remains influential in scientific and cultural contexts. Research on LSD declined due to cultural controversies by the 1960s, but has resurged since 2009. In 2024, the United States Food and Drug Administration designated LSD (code name MM120 or DT120) as a breakthrough therapy for generalized anxiety disorder. As of 2017, about 10% of people in the United States had used LSD at some point, with 0.7% having used it in the past year.
== Applications == Fourier-transform ion cyclotron resonance (FTICR) mass spectrometry is a high-resolution technique that can be used to determine masses with high accuracy. Many applications of FTICR-MS use this mass accuracy to help determine the composition of molecules based on accurate mass. This is possible due to the mass defect of the elements. FTICR-MS is able to achieve higher levels of mass accuracy than other forms of mass spectrometer, in part, because a superconducting magnet is much more stable than radio-frequency (RF) voltage. Another place that FTICR-MS is useful is in dealing with complex mixtures, such as biomass or waste liquefaction products, since the resolution (narrow peak width) allows the signals of two ions with similar mass-to-charge ratios (m/z) to be detected as distinct ions. This high resolution is also useful in studying large macromolecules such as proteins with multiple charges, which can be produced by electrospray ionization. For example, attomole level of detection of two peptides has been reported. These large molecules contain a distribution of isotopes that produce a series of isotopic peaks. Because the isotopic peaks are close to each other on the m/z axis, due to the multiple charges, the high resolving power of the FTICR is extremely useful. FTICR-MS is very useful in other studies of proteomics as well. It achieves exceptional resolution in both top-down and bottom-up proteomics.
Sources: en.wikipedia.org
Loratadine, sold under the brand name Claritin among others, is a medication used to treat allergies. This includes allergic rhinitis (hay fever) and hives. It is also available in drug combinations such as loratadine/pseudoephedrine, in which it is combined with pseudoephedrine, a nasal decongestant. It is taken orally. Common side effects include sleepiness, dry mouth, and headache. Serious side effects are rare and include allergic reactions, seizures, and liver problems. Use during pregnancy appears to be safe but has not been well studied. It is not recommended in children less than two years old. It is in the second-generation antihistamine family of medications. Loratadine was patented in 1980 and came to market in 1988. It is on the World Health Organization's List of Essential Medicines. Loratadine is available as a generic medication. In the United States, it is available over the counter. In 2023, it was the 105th most commonly prescribed medication in the United States, with more than 6 million prescriptions; and the combination with pseudoephedrine was the 300th most commonly prescribed medication in the United States, with more than 400,000 prescriptions.
1 July Scientists show why climate benefits from nature restoration are "dwarfed by the scale of ongoing fossil fuel emissions". A new CRISPR gene editing/repair tool alternative to fully active Cas9 is reported – Cas9-derived nickases mediated homologous chromosome-templated repair, applicable to organisms whose matching chromosome has the desired gene/s, which is demonstrated to be more effective than Cas9 and cause fewer off-target edits. 4 July – Scientists report that heatwaves in western Europe are increasing "three-to-four times faster compared to the rest of the northern midlatitudes over the past 42 years" and that certain atmospheric dynamical changes can explain their increase. 5 July – The Large Hadron Collider commences its Run 3 physics season. The LHCb collaboration observes three never-before-seen particles: a new kind of "pentaquark" and the first-ever pair of "tetraquarks", which includes a new type of tetraquark. Scientists based in Bengaluru’s Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) have found a novel substance termed “single-crystalline scandium nitride” that can transform infrared light into renewable energy. 6 July – A study suggests that the marginal effectiveness of a fourth COVID-19 vaccine dose (a second "booster") versus three doses can be 40% (24% to 52%) against severe disease outcomes. There is no scientific consensus about the efficacy and overall recommendabilities of a fourth dose. The CDC recommended such in March only for "certain immunocompromised individuals and people over the age of 50".
== Separation process and principle == The separation of compounds is due to the differences in their attraction to the stationary phase and because of differences in solubility in the solvent. Different compounds in the sample mixture travel at different rates due to the differences in their partition coefficients. Different solvents, or different solvent mixtures, give different separations. The retardation factor (RF) quantifies the results. It is the distance traveled by a given substance divided by the distance traveled by the mobile phase.
=== Media coverage === The many murders which were carried out by the Moroccan mafia were a turning point in criminal journalism across Belgium and the Netherlands. Although the Moroccan mafia is not the first criminal phenomenon in these countries, it is the first to receive both international and intensive media coverage. The Dutch virtual tax reforms of the 2010s encouraged the emergence of inexpensive print media, which could therefore be widely distributed and relayed. These broadcasts were the precursors of a trend that gained momentum after the assassination of journalist Martin Kok in 2016. The Dutch newspaper De Telegraaf benefited greatly from the public enthusiasm for the criminal war that was taking place in its cities, which received unprecedented media coverage. While some Dutch media outlets decided to censor the first and last names of the editors who published articles, other news outlets like De Telegraaf did not give into the panic, and refused to practice censorship. After the attacks on De Telegraaf and Panorama in 2017, lawyer Christien Wildeman stated:
Sources: en.wikipedia.org
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.