Everything below concerns Melanocortin receptor. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-06-04. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
| 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 |
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
Verification of a supplied batch generally combines a certificate of analysis with independent testing, because certificates are self-reported documents. A typical package includes a chromatographic trace, a mass spectrum, and a stated water or counter-ion content. Batch-to-batch consistency matters more than a single purity figure when results are compared across experiments. No single mandatory standard governs research-grade peptide release, so laboratories are expected to define their own acceptance criteria. Residual trifluoroacetate from purification is a frequently overlooked counter-ion.
Lyophilized material is chemically stable for extended periods when kept dry, cold, and protected from light. The powder is hygroscopic, so vials should be warmed to room temperature before opening to reduce condensation on the contents. Once dissolved, the peptide is far less stable because peptide bonds are susceptible to hydrolysis and the methionine residue can oxidize. Solutions are typically aliquoted and held at 2-8 °C for short intervals or frozen for longer ones, and repeated freeze-thaw cycles should be avoided.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
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.
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
Certain serpins spontaneously undergo the S to R transition without having been cleaved by a protease, to form a conformation termed the latent state. Latent serpins are unable to interact with proteases and so are no longer protease inhibitors. The conformational change to latency is not exactly the same as the S to R transition of a cleaved serpin. Since the RCL is still intact, the first strand of the C-sheet has to peel off to allow full RCL insertion. Regulation of the latency transition can act as a control mechanism in some serpins, such as PAI-1. Although PAI-1 is produced in the inhibitory S conformation, it "auto-inactivates" by changing to the latent state unless it is bound to the cofactor vitronectin. Similarly, antithrombin can also spontaneously convert to the latent state, as an additional modulation mechanism to its allosteric activation by heparin. Finally, the N-terminus of tengpin, a serpin from Thermoanaerobacter tengcongensis, is required to lock the molecule in the native inhibitory state. Disruption of interactions made by the N-terminal region results in spontaneous conformational change of this serpin to the latent conformation.
(R)-3,4-Methylenedioxy-N-methylamphetamine ([R]-MDMA), also known as (R)-midomafetamine or as levo-MDMA, is the (R)- or levorotatory (l-) enantiomer of 3,4-methylenedioxy-N-methylamphetamine (MDMA; midomafetamine; "ecstasy"), a racemic mixture of (R)-MDMA and (S)-MDMA. Like MDMA, (R)-MDMA is an entactogen or empathogen. It is taken by mouth. The drug is a serotonin–norepinephrine releasing agent (SNRA) and weak serotonin 5-HT2A receptor agonist. It has substantially less or no significant dopamine-releasing activity compared to MDMA and (S)-MDMA. In preclinial studies, (R)-MDMA shows equivalent therapeutic-like effects to MDMA, such as increased prosocial behavior, but shows reduced psychostimulant-like effects, addictive potential, and serotonergic neurotoxicity. In clinical studies, (R)-MDMA produces similar effects to MDMA and (S)-MDMA, but is less potent and has a longer duration. (R)-MDMA was first described in enantiopure form by 1978. Under the developmental code names EMP-01, developed by AtaiBeckley, and DT402 (formerly MM402), developed by Definium Therapeutics (formerly MindMed), it is under development for the treatment of post-traumatic stress disorder (PTSD), social phobia, and pervasive development disorders (PDDs) such as autism. It is thought that (R)-MDMA might have a better safety profile than MDMA itself whilst retaining its therapeutic benefits.
=== Clinical medicine === In clinical medicine, sterile test tubes with air removed, called vacutainers, are used to collect and hold samples of physiological fluids such as blood, urine, pus, and synovial fluid. These tubes are commonly sealed with a rubber stopper and often have a specific additive placed in the tube with the stopper color indicating the additive. For example, a blue-top tube is a 5 ml test tube containing sodium citrate as an anticoagulant, used to collect blood for coagulation and glucose-6-phosphate dehydrogenase testing. Small vials used in medicine may have a snap-top (also called a hinge cap) molded as part of the vial.
There are three common naming conventions for specifying one of the two enantiomers (the absolute configuration) of a given chiral molecule: the R/S system is based on the geometry of the molecule; the (+)- and (−)- system (also written using the obsolete equivalents d- and l-) is based on its optical rotation properties; and the D/L system is based on the molecule's relationship to enantiomers of glyceraldehyde. The R/S system is based on the molecule's geometry with respect to a chiral center. The R/S system is assigned to a molecule based on the priority rules assigned by Cahn–Ingold–Prelog priority rules, in which the group or atom with the largest atomic number is assigned the highest priority and the group or atom with the smallest atomic number is assigned the lowest priority. The (+) or (−) symbol is used to specify a molecule's optical rotation — the direction in which the polarization of light rotates as it passes through a solution containing the molecule. When a molecule is denoted dextrorotatory, it rotates the plane of polarized light clockwise and can also be denoted as (+). When it is denoted as levorotatory, it rotates the plane of polarized light counterclockwise and can also be denoted as (−). The Latin words for left are laevus and sinister, and the word for right is dexter (or rectus in the sense of correct or virtuous). The English word right is a cognate of rectus. This is the origin of the D/L and R/S notations and the employment of prefixes levo- and dextro- in common names. In some contexts, the prefixes ar- and es- are used in the names.
== External links == Understanding Pompe Disease - US National Institute of Arthritis and Musculoskeletal and Skin Diseases AGSD — Association of Glycogen Storage Disease in the United States AGSD-UK — Association of Glycogen Storage Disease in the UK AMDA — Acid Maltase Deficiency Association (Pompe disease) IPA — International Pompe Association IamGSD — International Association for Muscle Glycogen Storage Disease
Sources: en.wikipedia.org
Rockefeller University – then the Rockefeller Institute for Medical Research (established by Senior); Colonial Williamsburg (John Jr., Abby); Riverside Church (John Jr.); International House of New York (John Jr.); General Education Board – later the International Education Board (Senior); China Medical Board (John Sr., John Jr.); Bureau of Social Hygiene (John Jr.); Industrial Relations Counselors (John Jr.). John III was at one time a member of the Council on Foreign Relations, the Foreign Policy Association and the Institute of Pacific Relations, as well as being on the board of directors of Princeton University. In late 1950, he accompanied secretary of state John Foster Dulles and Douglas MacArthur on a trip to Japan to conclude a peace treaty, during which time he consulted with many Japanese leaders in practically every important sphere of that country's life. He was a prominent third-generation family philanthropist in his own right and founder of the Asia Society, the major institution he established in 1956 to foster greater cooperation between Asia and the United States. He also founded the Population Council in 1952, and a reconstituted Japan Society. In addition, he set up the United Negro College Fund for the ongoing education of African Americans, carrying on the family tradition in this area with his grandfather's funding of the education of black women at Spelman College in Atlanta. He was on his father's Advisory Committee in the family office, Room 5600.
Most ants are predatory and some prey on and obtain food from other social insects including other ants. Some species specialise in preying on termites (Megaponera and Neoponera) while a few Cerapachyinae prey on other ants. Some termites, including Nasutitermes corniger, form associations with certain ant species to keep away predatory ant species. The tropical wasp Mischocyttarus drewseni coats the pedicel of its nest with an ant-repellent chemical. It is suggested that many tropical wasps may build their nests in trees and cover them to protect themselves from ants. Other wasps, such as A. multipicta, defend against ants by blasting them off the nest with bursts of wing buzzing. Stingless bees (Trigona and Melipona) use chemical defences against ants. Flies in the Old World genus Bengalia (Calliphoridae) prey on ants and are kleptoparasites, snatching prey or brood from the mandibles of adult ants. Wingless and legless females of the Malaysian phorid fly (Vestigipoda myrmolarvoidea) live in the nests of ants of the genus Aenictus and are cared for by the ants.
== Therapeutic use == As a mast cell activator, the MCD peptide evokes large increases in antigen-specific serum immunoglobulin G (IgG) responses. Therefore, it is used as a vaccine adjuvant. MCD peptide analogs, such as [Ala12] MCD, provide a base for designing agents that can prevent IgE/Fc-RIa interactions and reduce allergic conditions.
Acute erythema nodosum Bowel-associated dermatosis–arthritis syndrome (bowel bypass syndrome, bowel bypass syndrome without bowel bypass, intestinal bypass arthritis–dermatitis syndrome) Marshall syndrome Neutrophilic dermatosis of the dorsal hands (pustular vasculitis of the dorsal hands) Neutrophilic eccrine hidradenitis Pyoderma gangrenosum Pyogenic arthritis–pyoderma gangrenosum–acne syndrome (PAPA syndrome) Rheumatoid neutrophilic dermatitis (rheumatoid neutrophilic dermatosis) Superficial granulomatous pyoderma Sweet's syndrome (acute febrile neutrophilic dermatosis) Sweet's syndrome-like dermatosis Vesicopustular dermatosis
Sources: en.wikipedia.org
Offenbarung als Kommunikation: Das Konzept wahy in Nasr Hamid Abu Zaids Mafhum an-nass, Frankfurt et al. 1996 (Peter Lang). Kermani, Navid (2000). Gott ist schön (in German). C.H.Beck. ISBN 978-3-406-46738-7. Nasr Hamid Abu Zaid: Ein Leben mit dem Islam, Freiburg 1999: Herder. Iran: Die Revolution der Kinder, Munich 2000: C. H. Beck. Dynamit des Geistes: Martyrium, Islam und Nihilismus, Göttingen 2002: Wallstein. Das Buch der von Neil Young Getöteten, Zurich 2002: Ammann: Cologne 2004; Kiepenheuer; Berlin 2013: Suhrkamp. Schöner Neuer Orient: Berichte von Städten und Kriegen, Munich 2003: C. H. Beck; Munich 2007: dtv. Toleranz: Drei Lesarten zu Lessings Märchen vom Ring im Jahre 2003 (with Angelika Overath and Robert Schindel), Göttingen 2003: Wallstein. Vierzig Leben, Zurich 2004: Ammann. Du sollst, Zurich 2005: Ammann. Der Schrecken Gottes Munich 2005: C. H. Beck. Strategie der Eskalation: Der Nahe Osten und die Politik des Westens, Göttingen 2005: Wallstein. Nach Europa, Zurich 2006: Ammann. Ayda, Bär und Hase (children's book), Vienna 2006: Picus. Mehdi Bazargan, Und Jesus ist sein Prophet: Der Koran und die Christen, German trans. from the Persian by Markus Gerhold, ed. and with an introduction by Navid Kermani, Munich 2006: C. H. Beck. Kurzmitteilung, Zurich 2007: Ammann. Wer ist Wir? Deutschland und seine Muslime, Munich 2009: C. H. Beck. Ausnahmezustände: Reisen in eine beunruhigte Welt, Munich 2013: C. H. Beck. Zwischen Koran und Kafka: West-östliche Erkundungen, Munich 2014: C. H. Beck. Ungläubiges Staunen: Über das Christentum, Munich 2015: C. H. Beck.
Clinical chemistry (also known as chemical pathology, clinical biochemistry or medical biochemistry) is a division in pathology and medical laboratory sciences focusing on qualitative tests of important compounds, referred to as analytes or markers, in bodily fluids and tissues using analytical techniques and specialized instruments. This interdisciplinary field includes knowledge from medicine, biology, chemistry, biomedical engineering, informatics, and an applied form of biochemistry (not to be confused with medicinal chemistry, which involves basic research for drug development). The discipline originated in the late 19th century with the use of simple chemical reaction tests for various components of blood and urine. Many decades later, clinical chemists use automated analyzers in many clinical laboratories. These instruments perform experimental techniques ranging from pipetting specimens and specimen labelling to advanced measurement techniques such as spectrometry, chromatography, photometry, potentiometry, etc. These instruments provide different results that help identify uncommon analytes, changes in light and electronic voltage properties of naturally occurring analytes such as enzymes, ions, electrolytes, and their concentrations, all of which are important for diagnosing diseases. Blood and urine are the most common test specimens clinical chemists or medical laboratory scientists collect for clinical routine tests, with a main focus on serum and plasma in blood. There are now many blood tests and clinical urine tests with extensive diagnostic capabilities.
== Pregnancy and nursing mothers == Nordazepam, like other benzodiazepines, easily crosses the placental barrier, so the drug should not be administered during the first trimester of pregnancy. In case of serious medical reasons, nordazepam can be given in late pregnancy, but the fetus, due to the pharmacological action of the drug, may experience side effects such as hypothermia, hypotonia, and sometimes mild respiratory depression. Since nordazepam and other benzodiazepines are excreted in breast milk, the substance should not be administered to mothers who are breastfeeding. Discontinuing of breast-feeding is indicated for regular intake by the mother.
Testosterone can be taken by a variety of different routes of administration. These include oral, buccal, sublingual, intranasal, transdermal (gels, creams, patches, solutions), vaginal (creams, gels, suppositories), rectal (suppositories), by intramuscular or subcutaneous injection (in oil solutions or aqueous suspensions), and as a subcutaneous implant. The pharmacokinetics of testosterone, including its bioavailability, metabolism, biological half-life, and other parameters, differ by route of administration. Likewise, the potency of testosterone, and its local effects in certain tissues, for instance the liver, differ by route of administration as well. In particular, the oral route is subject to a high first-pass effect, which results in high levels of testosterone in the liver and consequent hepatic androgenic effects, as well as low potency due to first-pass metabolism in the intestines and liver into metabolites like dihydrotestosterone and androgen conjugates. Conversely, this is not the case for non-oral routes, which bypass the first pass. Different testosterone routes and dosages can achieve widely varying circulating testosterone levels. For purposes of comparison with normal physiological circumstances, circulating levels of total testosterone in men range from about 250 to 1,100 ng/dL (mean 630 ng/dL) and in women range from about 2 to 50 ng/dL (mean 32 ng/dL). Testosterone levels decline with age in men.
Hazard research is published: researchers report gas stoves disperse nitrogen dioxide – associated with respiratory conditions such as asthma – at unsafe levels also outside kitchens for hours (3 May), a study reported large amounts of microplastic in brains with concentrations being much larger in samples from 2024 compared to 2016 (6 May), an experimental study finds GPT-4-based large language model-powered conversational search increases selective exposure compared to conventional Web search (11 May), a study indicates fish oil omega-3 supplements, widely taken due to associations of high omega-3 levels and good health or cognition, might be a substantial risk factor for atrial fibrillation and stroke except for those who took these already having atrial fibrillation (21 May), and researchers report continued transmission of bird flu within dairy cattle and show that their raw milk can infect mice (24 May).
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.
It is associated with the melanocortin receptor family, particularly subtypes found in the central nervous system. This interaction is separate from the adrenal pathway activated by full-length ACTH.