heptapeptide raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
多数实验室与市售的 Semax 以冻干粉形式提供。冻干粉通常建议保存在 -20 °C 或更低温度下，同时避免光照与反复升温。短期运输有时采用冷藏条件，但长期保存仍以冷冻为主。分包操作应尽量减少开盖次数，以降低吸湿和微生物污染的风险。开封后若未一次用完，建议在干燥环境中密封并尽快放回低温储存。
溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集，其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸，因此氧化风险相对突出。工作液一般主张现配现用，或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率，而关于最佳条件的公开数据并不统一。
常规纯度与身份确认依赖反相高效液相色谱，并辅以质谱测定分子量。氨基酸组成分析可用于验证序列构成，肽图分析则能进一步定位修饰或降解产物。杂质谱通常关注缺失序列肽、截短片段和氧化产物。不同方法的检出限并不相同，因此各实验室报告的纯度数值不宜直接横向比较。
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.
| Property | Value | Notes |
|---|---|---|
| 外观 | 白色至类白色粉末 | 常见于冻干制剂 |
| 溶解度 | 易溶于水 | 在极性溶剂中一般也可溶 |
| 建议储存温度 | -20 °C | 冻干粉，避光密封 |
| 常见分析手段 | 反相高效液相色谱 | 常与质谱联用 |
| 主要降解路径 | 水解与氧化 | 溶液状态更显著 |
Solid material is normally kept at minus 20 degrees Celsius in a sealed, desiccated container. Reconstituted solutions are less stable and are usually divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of activity. Light exposure is minimized by using amber glassware or foil wrapping. Published stability data for this peptide are sparse, so recommended storage conditions rest mainly on general practice for short synthetic peptides rather than on dedicated study.
Identity and purity are commonly assessed by reversed-phase high-performance liquid chromatography, with ultraviolet detection near 214 nanometers for the peptide backbone. Mass spectrometry, either electrospray or matrix-assisted laser desorption, confirms molecular mass and detects truncation or modification products. Amino acid analysis can verify composition. Because the sequence contains no strongly absorbing aromatic residue apart from phenylalanine, detection wavelengths are chosen carefully. Purity values above 95 percent are typical for research-grade material.
Quality documentation for research-grade peptide usually includes a certificate of analysis stating purity, identity, and residual counterion content. Batch-to-batch variation in purity and salt form is a recognized issue, and comparisons across suppliers require attention to the exact counterion, for example acetate versus trifluoroacetate. Sequence verification by tandem mass spectrometry provides stronger evidence than a single mass measurement. For any study reporting biological results, the analytical method and the measured purity should be stated explicitly. Independent verification of supplier claims is considered good practice.
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.
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.
==== Food ==== In the 1980s, W. R. Grace had owned the following restaurants: American Cafe, Del Taco, Coco's Bakery, El Torito, Hungry Tiger and various restaurants it had purchased from General Mills. In 1986, the company sold its restaurants and retained a 49 percent interest in the restaurant operations. The restaurant chains included Coco's, Houlihan's Old Place, Charley Brown's and Bristol Bar and Grill. The transaction also included El Torito Restaurants Inc., of which Grace had owned 73 percent. Charles H. Erhart Jr., vice chairman of Grace, said:While it is still too early to make a definitive estimate, we expect total proceeds to Grace to exceed $500 million from this transaction. In the process of leaving the restaurant business, the company later sold Del Taco to PepsiCo's Taco Bell in 1992.
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== Structure == Like other amino acids (not as a residue of a protein), cysteine exists as a zwitterion. Cysteine has l chirality in the older d/l notation based on homology to d- and l-glyceraldehyde. In the newer R/S system of designating chirality, based on the atomic numbers of atoms near the asymmetric carbon, cysteine (and selenocysteine) have R chirality, because of the presence of sulfur (or selenium) as a second neighbor to the asymmetric carbon atom. The remaining chiral amino acids, having lighter atoms in that position, have S chirality. Replacing sulfur with selenium gives selenocysteine.
==== MeSH E05.601.495 – immunoassay ==== MeSH E05.601.495.320 – immunoblotting MeSH E05.601.495.320.200 – blotting, western MeSH E05.601.495.350 – immunoenzyme techniques MeSH E05.601.495.350.170 – enzyme-linked immunosorbent assay MeSH E05.601.495.350.180 – enzyme multiplied immunoassay technique MeSH E05.601.495.380 – immunosorbent techniques MeSH E05.601.495.380.360 – enzyme-linked immunosorbent assay MeSH E05.601.495.380.810 – radioallergosorbent test MeSH E05.601.495.380.825 – radioimmunoprecipitation assay MeSH E05.601.495.380.830 – radioimmunosorbent test MeSH E05.601.495.639 – radioimmunoassay MeSH E05.601.495.639.405 – immunoradiometric assay MeSH E05.601.495.639.810 – radioallergosorbent test MeSH E05.601.495.639.825 – radioimmunoprecipitation assay MeSH E05.601.495.639.830 – radioimmunosorbent test
Sources: en.wikipedia.org
ASM Mammal Diversity Database; Archived December 25, 2022, at the Wayback Machine Biodiversitymapping.org – All mammal orders in the world with distribution maps; Archived September 26, 2016, at the Wayback Machine Paleocene Mammals; Archived February 3, 2024, at the Wayback Machine, a site covering the rise of the mammals, paleocene-mammals.de Evolution of Mammals; Archived January 25, 2024, at the Wayback Machine, a brief introduction to early mammals, enchantedlearning.com European Mammal Atlas EMMA; Archived January 25, 2024, at the Wayback Machine from Societas Europaea Mammalogica, European-mammals.org Marine Mammals of the World; Archived June 8, 2019, at the Wayback Machine – An overview of all marine mammals, including descriptions, both fully aquatic and semi-aquatic, noaa.gov Mammalogy.org; Archived March 1, 2020, at the Wayback Machine. The American Society of Mammalogists was established in 1919 for the purpose of promoting the study of mammals, and this website includes a mammal image library
== History == Viscofan was founded in 1975, which is also when it began producing and selling its products. In 1988, Viscofan acquired the food group IAN (Industrias Alimentarias de Navarra), aiming to improve its presence in the Spanish market. Viscofan continued its international expansion by acquiring the German company Naturin GmbH & Co. in 1990 and opening new commercial offices overseas. Additional acquisitions included Gamex in the Czech Republic (1995), Trificel in São Paulo, Brazil (1995), Koteksprodukt AD in Serbia (2005), and the assets of Sweden's AB Tripasin (2005). In 2006, Viscofan broadened its footprint in the Americas by acquiring the U.S. and Mexican assets of Teepak. In 2008, Viscofan expanded its cogeneration plant in Spain. That same year, the company launched Viscofan Bioengineering, a business unit that merges bioscience and engineering to develop collagen-based products intended for tissue repair. The Bioengineering unit is located in Weinheim (Germany), where Viscofan also maintains a production site for collagen casings and an additional cleanroom facility for manufacturing medical-grade collagen materials. In 2009, Viscofan established Viscofan Technology (Suzhou) Co. Ltd. in China. The following year, it opened a converting plant in the country. In 2012, the company created Viscofan Uruguay S.A., followed by the opening of a collagen extrusion plant in China in 2013 and another extrusion facility in Uruguay in 2014. In 2015, Viscofan sold the IAN Group to focus on its casings business.
=== 2006–2013: Rise to prominence and subsequent hiatus === Larter auditioned for the science fiction drama television series Heroes on NBC while living in Los Angeles. She played the characters of Niki Sanders, who suffered from dissociative identity disorder, and Tracy Strauss on the show created by Tim Kring. Larter's initial character Niki Sanders, was a wife, mother, and a former internet stripper from Las Vegas exhibiting superhuman strength and alternate personalities who go by the names of Jessica and Niki. "Ali read for the part and just owned it from the second she walked in," Kring said to the Chicago Tribune, "It was a very impressive audition." In the third and fourth seasons, Larter played the new character of Tracy Strauss, who possessed the ability to freeze objects and later, transform her body into water. Larter took on the title role in Marigold (2007), alongside Salman Khan, an Indian actor. The film was released in August 2007 and revolved around Marigold Lexington, an American actress (Larter) who goes to India and gets caught up in the exotic world of Bollywood. Filming took place in North India and London, commencing in June 2004. In an interview with the BBC, Larter remarked this role was "an opportunity to overcome my fear of singing and dancing because I have no professional training... I really focused on the character and loved this journey she went on and the experiences she had." She was paid a seven-figure salary for her part in the film.
Sources: en.wikipedia.org
一般不建议常温长期保存。多数说明指向 -20 °C 冷冻避光。常温运输通常被视为短期可接受，但会加快降解风险。
公开资料对此没有统一答案。普遍建议现配现用，或冷藏并在数日内用完。含甲硫氨酸的序列更易氧化，放置时间越长风险越高。
反相高效液相色谱是最常用的手段，配合质谱确认分子量。氨基酸组成分析和肽图分析可补充序列层面的验证。
It originated at the Institute of Molecular Genetics in Moscow during the 1980s. The work was carried out by a Russian research group that specialized in peptide neuropharmacology.