synthetic heptapeptide comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2025-08-28. Where a claim depends on a specific study, the study is described rather than over-claimed.
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
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。
Semax 是人工设计的七肽,序列为 Met-Glu-His-Phe-Pro-Gly-Pro,骨架取自促肾上腺皮质激素片段 ACTH(4-10)。它于二十世纪八十年代在苏联的分子遗传学研究机构内合成。设计目标是保留该片段与注意力和记忆相关的活性,同时剔除促皮质激素释放等内分泌作用。此后俄罗斯将其登记为药品并进入临床使用。
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | ACTH(4-7) analogue |
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Free N terminus, unmodified side chains |
| Molecular weight | 813.9 Da | Free base; salt forms differ |
| Appearance | White to off-white powder | Lyophilised solid |
| Solubility | Freely soluble in water | Hydrophilic; polar solvents preferred |
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.
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.
该化合物于二十世纪八十年代在俄罗斯被开发,相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性,而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示,这一方向促成了多个相关短肽的合成与筛选,而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
研究兴趣主要集中在神经营养因子相关的路径上,包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升,但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验,人体对照研究数量有限。因此,该化合物的作用机制在文献中属于活跃讨论,而非已经确立的定论。
Semax 是一种人工合成的七肽,氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro,单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物,但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly,Semax 替换了中间两个残基,并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
At its most fundamental level, inheritance in organisms occurs by passing discrete heritable units, called genes, from parents to offspring. This property was first observed by Gregor Mendel, who studied the segregation of heritable traits in pea plants, showing for example that flowers on a single plant were either purple or white—but never an intermediate between the two colors. The discrete versions of the same gene controlling the inherited appearance (phenotypes) are called alleles. In the case of the pea, which is a diploid species, each individual plant has two copies of each gene, one copy inherited from each parent. Many species, including humans, have this pattern of inheritance. Diploid organisms with two copies of the same allele of a given gene are called homozygous at that gene locus, while organisms with two different alleles of a given gene are called heterozygous. The set of alleles for a given organism is called its genotype, while the observable traits of the organism are called its phenotype. When organisms are heterozygous at a gene, often one allele is called dominant as its qualities dominate the phenotype of the organism, while the other allele is called recessive as its qualities recede and are not observed. Some alleles do not have complete dominance and instead have incomplete dominance by expressing an intermediate phenotype, or codominance by expressing both alleles at once. When a pair of organisms reproduce sexually, their offspring randomly inherit one of the two alleles from each parent.
The southern part of Africa was dominated in the 19th century by a set of struggles to create within it a single unified state. In 1868, Britain annexed Basutoland in the Drakensberg Mountains, following an appeal from Moshoeshoe I, the king of the Sotho people, who sought British protection against the Boers. While the Berlin Conference of 1884–1885 sought to draw boundaries between the European powers' African possessions, it also set the stage for further scrambles. Britain attempted to annex first the South African Republic in 1880, and then, in 1899, both the South African Republic and the Orange Free State. In the 1880s, Bechuanaland (modern Botswana) became the object of a dispute between the Germans to the west, the Boers to the east, and Britain's Cape Colony to the south. Although Bechuanaland had no economic value, the "Missionaries Road" passed through it towards territory farther north. After the Germans annexed Damaraland and Namaqualand (modern Namibia) in 1884, Britain annexed Bechuanaland in 1885. By 1877, the Transvaal government under President Thomas François Burgers was completely bankrupt due to the failed Pedi War and mounting foreign debts. When British official Sir Theophilus Shepstone annexed the republic in April of that year, the state treasury contained only 12 shillings and 6 pence. In the First Boer War of 1880–1881 the Boers of the Transvaal Republic proved skilful fighters in resisting Britain's attempt at annexation, causing a series of British defeats.
== Medical uses == Dielectric heating (diathermy) is used in medicine; the frequencies used typically lie in the ultrasonic, shortwave, and microwave ranges. Careless application, especially when the patient has implanted metal conductors (e.g. cardiostimulator leads), can cause burns of skin and deeper tissues and even death. Microwave damage to tissues can be intentionally exploited as a therapeutic technique, e.g. radiofrequency ablation and radiofrequency lesioning. Controlled destruction of tissue is performed for treatment of arrhythmia. Microwave coagulation can be used for some kinds of surgeries, e.g., stopping bleeding after a severe liver injury. Microwave heating seems to cause more damage to bacteria than equivalent thermal-only heating. However food reheated in a microwave oven typically reaches lower temperature than classically reheated, therefore pathogens are more likely to survive. Microwave heating of blood, e.g. for transfusion, is contraindicated, as it can cause hemolysis and hyperkalemia. Microwave heating is one of the methods for inducing hyperthermia for hyperthermia therapy. High-energy microwaves are used in neurobiology experiments to kill small laboratory animals (mice, rats) in order to fix brain metabolites without the loss of anatomical integrity of the tissue. The instruments used are designed to focus most of the power to the animal's head. The unconsciousness and death is nearly instant, occurring in less than one second, and the method is the most efficient one to fix brain tissue chemical activity.
== Further reading == Epstein, Noah; Chandran, Sheena; Chou, Loretta (2012). "Current Concepts Review: Intra-Articular Fractures of the Calcaneus". Foot & Ankle International. 33 (1): 79–86. doi:10.3113/FAI.2012.0079. ISSN 1071-1007. McKinley, Todd O; Borrelli, Joseph; D'Lima, Darryl D; Furman, Bridgette D; Giannoudis, Peter V (2010). "Basic Science of Intra-articular Fractures and Posttraumatic Osteoarthritis". Journal of Orthopaedic Trauma. 24 (9). Ovid Technologies (Wolters Kluwer Health): 567–570. doi:10.1097/bot.0b013e3181ed298d. ISSN 0890-5339. PMC 3662545.
Sources: en.wikipedia.org
Phosphorylation of Na+/K+-ATPase during the transport of sodium (Na+) and potassium (K+) ions across the cell membrane in osmoregulation to maintain homeostasis of the body's water content. ATP-binding cassette transporter
From about 1989 to 2018, Ontario has reported a deficit almost every year; the province's net debt increased to approximately $311.6 billion (by October 2018); and Ontario's net debt‐to‐GDP ratio grew from 13.4% to about 40.5% in 2018–19. According to an April 11, 2018 Royal Bank of Canada (RBC) report, which was based on figures provided by the Ford government, the revised estimate of Ontario's deficit was $11.7 billion in 2018–2019 and it was projected to decrease by $1.4 billion in 2019–2020 mainly because of "the removal of the $1 billion contingency reserve." At that time, it was projected that the deficit would be "completely eliminated in 2023–2024 with a small surplus of $0.3 billion." By October 2019, the Financial Accountability Officer, Weltman, said that the FAO had been in error when they—and the Ford government—had projected a $11.7-billion deficit that was reported in the spring 2019 budget. By June 2018, Ontario had "Canada's second-highest public debt per person and a growing budget deficit", according to The Economist. In October 2018, the Ontario Finance Department reported that Ontario's public debt per person, at $23,014, had surpassed that of Quebec at $21,606 in the fiscal year 2017–2018. Newfoundland and Labrador's public debt per capita, at $27,761, was the highest in Canada. By 2019, the Ontario Chamber of Commerce reported that Ontario's debt was over $348 billion—representing about 41% of provincial GDP of almost $850 billion. Ontario's GDP is much larger than any of the other provinces and is almost half of Canada's GDP.
=== Redistribution of pressure === An important aspect of care for most people at risk for pressure ulcers and those with bedsores is the redistribution of pressure so that no pressure is applied to the pressure ulcer. In the 1940s Ludwig Guttmann introduced a program of turning paraplegics every two hours thus allowing bedsores to heal. Previously such individuals had a two-year life-expectancy, normally succumbing to blood and skin infections. Guttmann had learned the technique from the work of Boston physician Donald Munro. There is lack of evidence on prevention of pressure ulcer whether the patient is put in 30 degrees position or at the standard 90 degrees position. Nursing homes and hospitals usually set programs in place to avoid the development of pressure ulcers in those who are bedridden, such as using a routine time frame for turning and repositioning to reduce pressure. The frequency of turning and repositioning depends on the person's level of risk. Various interventions have been developed to redistribute pressure, including the use of different bed mattresses, support surfaces, and the use of static chairs.
== Public awareness and solutions == Third-hand smoke is a relatively newly postulated and initially controversial concept, and public awareness of it is lower than that of passive smoke. A 2013 study with six focus groups in metro and rural Georgia (USA) asked participants whether they had heard of THS, most of the participants had not heard about it and did not know what third-hand smoke was. Research on THS is growing, but it does not compare to the 40 years of research on the effects of passive smoke. Yet, it is estimated that 5%-60% of passive smoke-related harm may be attributable to third-hand smoke exposure. THS poses such a risk because its exposure can linger much longer than passive smoke. Third-hand smoke-contaminated surfaces like carpet, walls, and car interiors are also especially hard to clean, whereas passive smoke can be removed with ventilation. Smoking rates in the United States have fallen considerably from 42.4% in 1965 to 17.8% in 2016. However, the downward trend is slowing, and it is estimated that 23% to 42% of adults in America with low education or living in poverty still smoke. This exposes millions of nonsmokers, many of whom are children. THS awareness campaigns are growing and primarily focus on the health risks for young children. A 2014 study published in Pediatrics demonstrated that parents are more likely to attempt to quit smoking if they become convinced that third-hand smoke is harmful to children and are more likely to have smoke-free home and car policies if they are aware of the dangers of third-hand smoke.
== Related conditions == Disorders that are clinically similar are konzo and Lytico-bodig disease. Konzo means "tied legs" in the Yaka language, and is common in some African people in central and eastern parts of the continent who are consuming diets poor in protein. The possible molecule causing this problem is thiocyanate, which stimulates AMPA receptors.
Sources: en.wikipedia.org
It is a synthetic seven-amino-acid peptide built from the ACTH(4-7) sequence plus a Pro-Gly-Pro tail. It belongs to the family of short ACTH fragments studied for nervous-system effects. Its backbone contains only standard amino acids.
It contains the 4-7 fragment of adrenocorticotropic hormone extended at the C terminus. That truncation removes the region associated with steroidogenic activity. The design intent was to keep neurotrophic properties while avoiding full hormonal effects.
No natural source of the intact heptapeptide is known. It is produced by solid-phase peptide synthesis. Some related ACTH fragments arise as hormone processing products, but the Pro-Gly-Pro extension is a designed addition rather than a natural sequence.
不存在。它是依据 ACTH 的一段序列人工设计的分子,天然蛋白质中找不到与之完全相同的七肽。名称属于研究代号,而非天然物质名。