A practical reference on Semax: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-07-04. Anything still debated is marked as such rather than presented as settled.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
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.
Semax is normally supplied as a lyophilized powder, and that form is the most stable. Suppliers commonly recommend storage at -20 °C in a desiccated container protected from light, with short-term handling at room temperature limited to weighing and transfer. Powder that has absorbed moisture degrades faster, so vials should be warmed to ambient temperature before opening to prevent condensation on the contents. Hygroscopic behavior is typical of short hydrophilic peptides, and humidity control matters more than temperature alone for long-term retention.
Once dissolved, the peptide is considerably less stable than the solid. Aqueous solutions are usually prepared at neutral to slightly acidic pH, filtered, and divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are a common cause of avoidable loss and are best prevented by never refreezing a thawed aliquot. Adsorption to plastic and glass surfaces can lower the measured concentration of dilute solutions, particularly below roughly 0.1 mg/mL. Buffer choice, salt content, and container material all influence how much peptide remains detectable after storage.
Identity and purity are established with standard peptide methods. Reversed-phase HPLC with ultraviolet detection near 214 nm resolves the parent peak from deletion and truncation byproducts, and reports typically quote a main-peak percentage. Mass spectrometry by electrospray or MALDI-TOF confirms the expected molecular mass, while amino acid analysis or peptide mapping can verify composition when the sequence itself is in question. A certificate of analysis that pairs a chromatogram with a mass spectrum is more informative than a purity figure alone. Counter-ion content and residual solvents are separate specifications and are frequently omitted.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Free acid form of the heptapeptide; depends on terminal groups |
| Molecular mass | About 813.9 g/mol | Average mass used for mass spectrometry confirmation |
| Appearance | White to off-white solid | Supplied as a lyophilised powder; hygroscopic |
| Solubility class | Freely soluble in aqueous media | Water, saline, and phosphate buffers; limited organic solubility |
| Typical storage temperature | -20 degrees Celsius | Long term and dry; short working periods may use 2 to 8 degrees Celsius |
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.
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.
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.
Stability depends heavily on physical state. Lyophilized powder held dry, cold and dark retains its content over long periods, whereas dissolved peptide begins to change within days at room temperature. The most cited degradation route is oxidation of the methionine residue, which converts the peptide to a sulfoxide form that elutes differently on chromatography. Hydrolysis of amide bonds and adsorption onto container walls contribute smaller losses. Buffers that exclude oxygen from the headspace slow the oxidation pathway, but no single condition prevents all change indefinitely.
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应，Semax 属于这一路线。鼻内给药是其主要使用方式，俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上，样本规模与终点设置同西方试验惯例存在差异，国际同行对其临床证据的强度看法不一。
各国监管态度分化明显。俄罗斯按处方药管理，部分东欧国家留有使用记录；欧盟与美国未批准其作为药物上市，市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录，跨境携带则受目的地药品法规约束。
=== Sandia National Laboratories and implantable insulin pump development === In parallel with early academic and commercial efforts, significant development of implantable insulin delivery systems was carried out at Sandia National Laboratories in collaboration with the University of New Mexico School of Medicine during the late 1970s and early 1980s. This work focused on the design of an electronically controlled, remotely programmable insulin infusion system intended to more closely replicate the physiological function of the human pancreas. The Sandia–UNM system built upon earlier external insulin pumps and incorporated engineering approaches derived from high-reliability systems, including precise flow control and programmable delivery rates. The implantable device was tested in animal models and subsequently implanted in human patients beginning in January 1981, with additional implantations reported in early 1982. Key engineering contributions to the system were made by a multidisciplinary team at Sandia, including Gary A. Carlson, Raymond E. Bair, John I. Gaona Jr., Jerry T. Love, and Ruben S. Urenda, who co-authored foundational technical reports describing the design and operation of the implantable, remotely programmable insulin infusion system. Earlier engineering work on insulin delivery systems by members of the Sandia–UNM collaboration was also described in peer-reviewed literature, including analysis of system design considerations such as flow control, programmability, and reliability.
==== Hermaphroditism ==== Some teleost species are hermaphroditic, which can come in two forms: simultaneous and sequential. In the former, both spermatozoa and eggs are present in the gonads. Simultaneous hermaphroditism typically occurs in species that live in the ocean depths, where potential mates are sparsely dispersed. Self-fertilisation is rare and has only been recorded in two species, Kryptolebias marmoratus and Kryptolebias hermaphroditus. With sequential hermaphroditism, individuals may function as one sex early in their adult life and switch later in life. Species with this condition include parrotfish, wrasses, sea basses, flatheads, sea breams and lightfishes. Protandry is when an individual starts out male and becomes female while the reverse condition is known as protogyny, the latter being more common. Changing sex can occur in various contexts. In the bluestreak cleaner wrasse, where males have harems of up to ten females, if the male is removed the largest and most dominant female develops male-like behaviour and eventually testes. If she is removed, the next ranking female takes her place. In the species Anthias squamipinnis, where individuals gather into large groups and females greatly outnumber males, if a certain number of males are removed from a group, the same number of females change sex and replace them. In clownfish, individuals live in groups and only the two largest in a group breed: the largest female and the largest male. If the female dies, the male switches sexes and the next largest male takes his place.
== Contraindications == Contraindications to subcutaneous injections primarily depend on the specific medication being administered. Doses which would require more than 2 mL to be injected at once are not administered subcutaneously. Medications which may cause necrosis or otherwise be damaging or irritating to tissues should also not be administered subcutaneously. An injection should not be given at a specific site if there is inflammation or skin damage in the area.
Sources: en.wikipedia.org
The three substrates of this enzyme are loganin, reduced nicotinamide adenine dinucleotide phosphate (NADPH), and oxygen. Its products are secologanin, oxidised NADP+, and water. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with oxygen as acceptor. The systematic name of this enzyme class is loganin:oxygen oxidoreductase (ring-cleaving). It is a member of the cytochrome P450 protein superfamily and participates in indole and ipecac alkaloid biosynthesis.
The Schleswig-Holstein War Between Denmark and the German States. Leonaur Limited. ISBN 978-1-78282-522-7. Schietzel, Kurt (2022). Unearthing Hedeby: An Archaeological Exploration of the Early Medieval Settlement of Hedeby : Documentation and Chronicle 1963-2013. Wachholtz. ISBN 978-3-529-01795-7. Bregnsbo, Michael; Jensen, Kurt Villads (2016). Schleswig Holstein: Contested Region(s) Through History. University Press of Southern Denmark. ISBN 978-87-7674-870-8. Svendsen, Nick (October 2012). Generals of the Danish Army in the First and Second Schleswig-Holstein Wars, 1848-50 And 1864: Rye, Du Plat, Schleppegrell. Helion, Limited. ISBN 978-1-908916-46-4. Svendsen, Nick (19 July 2010). The First Schleswig-Holstein War 1848-50. Helion and Company. ISBN 978-1-910294-19-2.
The demand for indigo in the 19th century is indicated by the fact that in 1897, 7,000 km2 (2,700 sq mi) were dedicated to the cultivation of indican-producing plants, mainly in India. By comparison, the country of Luxembourg is 2,586 km2 (998 sq mi). In Europe, indigo remained a rare commodity throughout the Middle Ages. A chemically identical dye derived from the woad plant (Isatis tinctoria) was used instead. In the late 15th century, the Portuguese explorer Vasco da Gama discovered a sea route to India. This led to the establishment of direct trade with India, the Spice Islands, China, and Japan. Importers could now avoid the heavy duties imposed by Persian, Levantine, and Greek middlemen and the lengthy and dangerous land routes which had previously been used. Consequently, the importation and use of indigo in Europe rose significantly. Much European indigo from Asia arrived through ports in Portugal, the Netherlands, and England. Many indigo plantations were established by European powers in tropical climates. Spain imported the dye from its colonies in Central and South America, and it was a major crop in Haiti and Jamaica, with much or all of the labor performed by enslaved Africans and African Americans. Indigo plantations also thrived in the Virgin Islands. However, France and Germany outlawed imported indigo in the 16th century to protect the local woad dye industry. In central Europe, indigo resist dyeing is a centuries-old skill that has received UNESCO Intangible Cultural Heritage of Humanity recognition.
Sources: en.wikipedia.org
=== Gower 1959 and Coventry 1964 === Heseltine contested the safe Labour seat of Gower at the October 1959 general election. He had been the only applicant for the Conservative (technically, Conservative and National Liberal) candidacy. He would at times attend Labour meetings and attempt to heckle the speakers, including Aneurin Bevan and the Labour candidate Ifor Davies, whom he kept trying to challenge to a debate. He obtained plenty of publicity in the local paper and obtained a swing to the Conservatives slightly better than the national average. In 1961 Heseltine was one of 29 applicants—of whom half were interviewed—for the Conservative candidacy in the marginal constituency of Coventry North. He clinched the selection after bringing his fiancée Anne Williams to the meeting. He got on well with the incumbent Labour member Maurice Edelman (whose daughter was a friend of Anne Heseltine, as she became in 1962) and they met for dinner sometimes during the campaign. Many of his Oxford contemporaries had already entered Parliament, but, to his disappointment, in the 1964 general election he was defeated by 3,530 votes. The swing to Labour was slightly less than the national average.
== Synthesis == The traditional route to dithiothreitol (and its isomer dithioerythritol) is sulfidation of the extremely lachrymatory 1,4-Dibromobut-2-ene. Modern industrial syntheses instead use related epoxides and hydrogen sulfide.
== Insulin resistance == Activation of PKC-θ by diacylglycerol may cause insulin resistance in muscle by decreasing IRS1-associated PI3K activity. Similarly, activation of PKCε by diacyglycerol may cause insulin resistance in the liver.
Sources: en.wikipedia.org
It is described as a synthetic analogue of the ACTH(4–10) fragment, a short segment of adrenocorticotropic hormone. Its sequence differs from that fragment and includes two proline residues, which influence stability and behaviour in solution.
It appears in Russian pharmaceutical listings as a nasal formulation, but it is not an authorised medicine in the United States or the European Union. Outside those markets it is normally encountered as a research chemical rather than a prescription product.
Laboratory and animal work points to melanocortin signalling and changes in neurotrophic factor levels, especially brain-derived neurotrophic factor. The exact receptor targets and the degree to which these findings transfer to humans are still unresolved.
Each freeze-thaw cycle can degrade a fraction of the peptide and promote aggregation. Dividing a stock solution into single-use volumes removes repeated cycling as a variable. It also limits the time a thawed solution spends at room temperature.