This is a working overview of heptapeptide, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-05-13 and is reviewed periodically as new material appears.
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。
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.
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
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.
| Property | Value | Notes |
|---|---|---|
| 结构类别 | 线性合成七肽 | 无环化结构，不含二硫键 |
| 氨基酸序列 | Met-Glu-His-Phe-Pro-Gly-Pro | N 端为甲硫氨酸 |
| 分子量 | 约 814 Da | 游离碱形式的计算值 |
| 外观 | 白色至类白色粉末 | 具吸湿性 |
| 溶解性 | 易溶于水 | 亦可溶于甲醇等极性溶剂 |
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.
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 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。
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。
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.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
==== Extraterrestrial ==== PAHs are prevalent in the interstellar medium (ISM) of galaxies in both the nearby and distant Universe and make up a dominant emission mechanism in the mid-infrared wavelength range, containing as much as 10% of the total integrated infrared luminosity of galaxies. PAHs generally trace regions of cold molecular gas, which are optimum environments for the formation of stars. NASA's Spitzer Space Telescope and James Webb Space Telescope include instruments for obtaining both images and spectra of light emitted by PAHs associated with star formation. These images can trace the surface of star-forming clouds in our own galaxy or identify star forming galaxies in the distant universe. In June 2013, PAHs were detected in the upper atmosphere of Titan, the largest moon of the planet Saturn.
The reason why α-amino acids are used in proteins has been linked to their frequency in meteorites and prebiotic experiments. An initial speculation on the deleterious properties of β-amino acids in terms of secondary structure turned out to be incorrect.
A 90,000 round artillery preparation fire on Iraqi defensive positions preceded the major ground assault, lasting 2.5 hours. 1st Infantry Division Artillery, which included 4-3 FA battalion, was decisive during artillery combat operations performing multiple raids and fire missions. These combat operations resulted in the destruction of 50 enemy tanks, 139 APCs, 30 air defense systems, 152 artillery pieces, 27 missile launchers, 108 mortars, and 548 wheeled vehicles, 61 trench lines and bunker positions, 92 dug in and open infantry targets, and 34 logistical sites. The ground campaign consisted of three or possibly four of the largest tank battles in American military history. The battles at 73 Easting, Norfolk, and Medina Ridge are well noted for their historical significance. Some consider the Battle of Medina Ridge the largest tank battle of the war. Other sources consider the Battle of Norfolk the largest tank battle of the war and the second largest tank battle in American military history, behind the Battle of the Bulge. The U.S. Marine Corps also fought the biggest tank battle in its history at Kuwait International Airport. The U.S. 3rd Armored Division also fought a significant battle at Objective Dorset not far from where the Battle of Norfolk was taking place. The U.S. 3rd Armored Division destroyed approximately 300 enemy combat vehicles during this particular encounter with Iraqi forces. The U.S. VII Corps was the primary combat formation of the coalition forces.
Sources: en.wikipedia.org
=== Plant-based medications === There has been a number of alternative therapies experimented in ayurvedic medicine with plant-based products, although none have provided good evidence of efficacy. A recent study showed that the stromal processing peptidase (SPP), a synthetic enzyme found in plant chloroplasts, prevented the aggregation of proteins associated with Huntington's disease. However, repeat studies and clinical validation are needed to confirm its true therapeutic potential.
=== Myelography === For patients with recalcitrant spontaneous intracranial hypotension and no leak found on conventional spinal imaging, digital subtraction myelography, CT myelography and dynamic myelography (a modified conventional myelography technique) should be considered to rule out a CSF-venous fistula. In addition, presence of a hyperdense paraspinal vein should be investigated in imaging as it is highly suggestive of a CSF venous fistula.
==== Correspondence to effects ==== Co-administration of quinidine, a potent CYP2D6 enzyme inhibitor, with tramadol, a combination which results in markedly reduced levels of desmetramadol, was found not to significantly affect the analgesic effects of tramadol in human volunteers. However, other studies have found that the analgesic effects of tramadol are significantly decreased or even absent in CYP2D6 poor metabolizers. The analgesic effects of tramadol are only partially reversed by naloxone in human volunteers, hence indicating that its opioid action is unlikely the sole factor; tramadol's analgesic effects are also partially reversed by α2-adrenergic receptor antagonists such as yohimbine, the 5-HT3 receptor antagonist ondansetron, and the 5-HT7 receptor antagonists SB-269970 and SB-258719. Pharmacologically, tramadol is similar to tapentadol and methadone in that it not only binds to the MOR, but also inhibits the reuptake of serotonin and norepinephrine due to its action on the noradrenergic and serotonergic systems, such as its "atypical" opioid activity. Tramadol has inhibitory actions on the 5-HT2C receptor. Antagonism of 5-HT2C could be partially responsible for tramadol's reducing effect on depressive and obsessive–compulsive symptoms in patients with pain and co-morbid neurological illnesses. 5-HT2C blockade may also account for its lowering of the seizure threshold, as 5-HT2C knockout mice display significantly increased vulnerability to epileptic seizures, sometimes resulting in spontaneous death.
Sources: en.wikipedia.org
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。
Semax 对应 ACTH 第 4 至第 10 位的片段，并在两端做了替换与延长，使其不再具备促肾上腺皮质激素的典型内分泌活性。这一改动同时改变了它在体内的稳定性与分布特征。
俄罗斯将其列为处方药物，需要医生开具处方。多数其他国家把它当作研究化合物，不能作为药品销售或宣称疗效。具体合法性取决于当地法规。
Registered medical products are most often 0.1% nasal drops. Research suppliers ship lyophilized powder, usually in milligram quantities, which is dissolved before use. The active peptide is the same in both cases; presentation and excipients differ.