The short version of heptapeptide fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-05-11. Anything still debated is marked as such rather than presented as settled.
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。
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
| Property | Value | Notes |
|---|---|---|
| 化学类别 | 合成七肽 | ACTH(4-10) 结构类似物 |
| 氨基酸序列 | Met-Glu-His-Phe-Pro-Gly-Pro | 单字母写作 MEHFPGP |
| 分子量 | 约 813.9 Da | 随确切形式和盐型略有变化 |
| 常见同义词 | ACTH(4-10) 类似物 | 俄语文献称 Семакс |
| 开发来源 | 俄罗斯 | 二十世纪八十年代 |
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.
The compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.
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.
The Keewatin Region was a district of the Northwest Territories, in use as an administrative and statistical division until the creation of Nunavut in 1999. The majority of Keewatin Region fell on the Nunavut side of the boundary and was reconstituted as Kivalliq Region within the new territory, while a strip on the region's west side remaining in the NWT was transferred to Fort Smith Region. Kivalliq continues to be referred to as "Keewatin Region, Nunavut" in some circumstances, such as by Statistics Canada. The regional seat of the Keewatin Region was Rankin Inlet.
Plants rely on micronutrients to build many essential proteins. In fact, every process that supports the growth of a plant is mediated by some protein which contains one of the many micronutrients. For example, Mn is an essential micronutrient for many plants because it builds the structure of photosystem II which splits water molecules to harness energy from electrons. Inadequate micronutrient uptake can result in deficiencies and even mortality in extreme cases. Alternatively, elevated concentrations of micronutrients in soils can result in toxicity.
The Battle of Marengo, which largely ended the War of the Second Coalition, was fought with fewer than 60,000 men on both sides. The Battle of Austerlitz which ended the War of the Third Coalition involved fewer than 160,000 men. The Battle of Friedland which led to peace with Russia in 1807 involved about 150,000 men. After these defeats, the continental powers developed various forms of mass conscription to allow them to face France on even terms, and the size of field armies increased rapidly. The Battle of Wagram of 1809 involved 300,000 men, and 500,000 fought at Leipzig in 1813, of whom 150,000 were killed or wounded. About a million French soldiers became casualties (wounded, invalided or killed), a higher proportion than in the First World War. The European total may have reached 5,000,000 military deaths, including disease. France had the second-largest population in Europe by the end of the 18th century (28 million, as compared to Britain's 12 million and Russia's 35 to 40 million). It was well poised to take advantage of the levée en masse. Before Napoleon's efforts, Lazare Carnot played a large part in the reorganization of the French Revolutionary Army from 1793 to 1794—a time which saw previous French misfortunes reversed, with Republican armies advancing on all fronts.
Sources: en.wikipedia.org
Although various different techniques of acupuncture practice have emerged, the method used in traditional Chinese medicine (TCM) seems to be the most widely adopted in the US. Traditional acupuncture involves needle insertion, moxibustion, and cupping therapy, and may be accompanied by other procedures such as feeling the pulse and other parts of the body and examining the tongue. Traditional acupuncture involves the belief that a "life force" (qi) circulates within the body in lines called meridians. The main methods practiced in the UK are TCM and Western medical acupuncture. The term Western medical acupuncture is used to indicate an adaptation of TCM-based acupuncture which focuses less on TCM. The Western medical acupuncture approach involves using acupuncture after a medical diagnosis. Limited research has compared the contrasting acupuncture systems used in various countries for determining different acupuncture points, and thus there is no defined standard for acupuncture points. In traditional acupuncture, the acupuncturist decides which points to treat by observing and questioning the patient to make a diagnosis according to the tradition used. In TCM, the four diagnostic methods are: inspection, auscultation and olfaction, inquiring, and palpation. Inspection focuses on the face and particularly on the tongue, including analysis of the tongue placement, size, shape, tension, color and coating, and the absence or presence of teeth marks around the edge. Auscultation and olfaction involve listening for particular sounds, such as wheezing, and observing body odor.
An eye dropper, also called Pasteur pipette or simply dropper, is a device used to transfer small quantities of liquids. They are used in the laboratory and also to dispense small amounts of liquid medicines. A very common use is to dispense eye drops into the eye. The commonly recognized form is a glass tube tapered to a narrow point (a pipette) and fitted with a rubber bulb at the top, although many styles of both plastic and glass droppers exist. The combination of the pipette and rubber bulb has also been referred to as a teat pipette. The Pasteur pipette name is from the French scientist Louis Pasteur, who used a variant of them extensively during his research. In the past, there was no equipment to transfer a chemical solution without exposing it to the external environment. The hygiene and purity of chemical compounds is necessary for the expected result of each experiment. The eye dropper, both glass and plastic types, can be sterilized and plugged with a rubber bulb at the open end of the pipette preventing any contamination from the atmosphere. Generally, they are considered cheap enough to be disposable, however, so long as the glass point is not chipped, the eye dropper may be washed and reused indefinitely.
==== In males ==== It is secreted from the Sertoli cells, located in the seminiferous tubules inside the testes. Androgens stimulate inhibin production; this protein may also help to locally regulate spermatogenesis.
Sources: en.wikipedia.org
==== Regional hubs ==== UPS has five regional hubs in the Asia-Pacific region, located in Hong Kong, Japan, Korea, Malaysia, and Thailand. These hubs serve as major sorting and distribution centers for packages moving within and between regions.
Tofu flavor is generally described as bland, which is generated during the grinding and cooking process, and either a "hot grind" or a "cold grind" can be used to influence the taste. The hot grind method reduces the beany flavor by inactivating the lipoxygenase enzyme in the soy protein that is known to generate off flavors. Eliminating these flavors makes tofu that is "bland". If a cold grind is used lipoxygenase remains and produces the aldehyde, alcohol, and ester volatile compounds that create beany notes.
The largest use of vanillin is as a flavoring, usually in sweet foods. The ice cream and chocolate industries together comprise 75% of the market for vanillin as a flavoring, with smaller amounts being used in confections and baked goods. Vanillin is also used in the fragrance industry, in perfumes, and to mask unpleasant odors or tastes in medicines, livestock fodder, and cleaning products. It is also used in the flavor industry, as a very important key note for many different flavors, especially creamy profiles such as cream soda. Additionally, vanillin can be used as a general-purpose stain for visualizing spots on thin-layer chromatography plates. This stain yields a range of colors for these different components.
=== Control of FSH and LH === At the pituitary, GnRH stimulates the synthesis and secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). These processes are controlled by the size and frequency of GnRH pulses, as well as by feedback from androgens and estrogens. Low-frequency GnRH pulses are required for FSH release, whereas high-frequency GnRH pulses stimulate LH pulses in a one-to-one manner. There are differences in GnRH secretion between females and males. In males, GnRH is secreted in pulses at a constant frequency; however, in females, the frequency of the pulses varies during the menstrual cycle, and there is a large surge of GnRH just before ovulation. GnRH secretion is pulsatile in all vertebrates, and is necessary for correct reproductive function. Thus, a single hormone, GnRH1, controls a complex process of follicular growth, ovulation, and corpus luteum maintenance in the female, and spermatogenesis in the male.
Sources: en.wikipedia.org
不是。Semax 是完全人工合成的七肽,自然界中没有对应的已知肽段。它的设计灵感来自促肾上腺皮质激素片段 ACTH(4-10),但序列经过了替换和延长。
Semax 被描述为 ACTH(4-10) 的结构类似物,两者共享部分序列特征。它保留了该片段的部分神经相关活性方向,但去除了完整片段带来的激素释放效应。二者并非同一物质,也不能互相替代。
加入的 Pro-Gly-Pro 三肽被普遍认为能提升分子对蛋白水解酶的稳定性。这种设计让短肽在体内维持时间更长。具体延长的程度以及不同组织中是否一致,文献中仍存在不同报告。
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.