This is a working overview of nasal drops, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-02-11. Anything still debated is marked as such rather than presented as settled.
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.
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.
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 |
|---|---|---|
| Molecular formula | C37H51N9O10S | Seven-residue peptide |
| Molecular mass | 813.9 Da | Monoisotopic value |
| Appearance | White to off-white powder | Lyophilized form |
| Solubility | Freely soluble in water | Also soluble in saline and polar solvents |
| Storage (dry) | -20 °C or lower | Desiccated, protected from light |
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。
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.
=== Prodrome phase === The prodrome, or premonitory phase, of migraine is generally defined as the 48 hours preceding the pain or aura phases of an attack. Estimates of how often prodromal symptoms occur vary widely. Around 29% of people with migraine in population-based studies report at least one premonitory symptom. Amongst individuals who attend headache clinics, around 66% of people report premonitory symptoms. Symptoms may vary widely, and can include altered mood, irritability, depression or euphoria, fatigue, craving for certain food(s), difficulty speaking or reading, yawning, stiff muscles (especially in the neck), constipation or diarrhea, and sensitivity to smells or noise. Premonitory symptoms may occur in both migraine without aura and migraine with aura.
Healthcare centres, including clinics, doctor's offices, urgent care centers and ambulatory surgery centers, serve as first point of contact with a health professional and provide outpatient medical, nursing, dental, and other types of care services.
The yR design approach provides an unvarying reaction site with regard to both (a) distance between reactants and (b) sequence environment surrounding the reaction site. Furthermore, the intimate connection between the code and the BB on the oligo-BB moieties which are mixed combinatorially in a single pot confers a high fidelity to the encoding of the library. The code of the synthesized products, furthermore, is not preset, but rather is assembled combinatorially and synthesized in synchronicity with the innate product.
== External links == Histology image: 12_02 at the University of Oklahoma Health Sciences Center - "epiglottis" Histology image: 02901loa – Histology Learning System at Boston University Histology at ucsd.edu Archived 2012-02-05 at the Wayback Machine Anatomy Atlases – Microscopic Anatomy, plate 03.42
Sources: en.wikipedia.org
== Iron-57 == 57Fe is widely used in Mössbauer spectroscopy and the related nuclear resonance vibrational spectroscopy due to the low natural variation in energy of the 14.4 keV nuclear transition. The transition was famously used to make the first definitive measurement of gravitational redshift, in the 1960 Pound–Rebka experiment.
=== Drug interactions === Clinical drug-drug interactions with dalbavancin have not been studied, and dalbavancin does not appear to interact with cytochrome P450 substrates, inhibitors, or inducers. It was found to have an in vitro synergistic interaction with the antimicrobial oxacillin, but the clinical significance of this interaction has yet to be established.
Used in biological sequence analysis: Genbank, UniProt Used in structure analysis: Protein Data Bank (PDB) Used in finding Protein Families and Motif Finding: InterPro, Pfam Used for Next Generation Sequencing: Sequence Read Archive Used in Network Analysis: Metabolic Pathway Databases (KEGG, BioCyc), Interaction Analysis Databases, Functional Networks Used in design of synthetic genetic circuits: GenoCAD
∇⋅ is divergence, ρ is the density of the amount q (i.e. the quantity q per unit volume), j is the flux of q (i.e. j = ρv, where v is the vector field describing the movement of the quantity q), t is time, σ is the generation of q per unit volume per unit time. Terms that generate q (i.e., σ > 0) or remove q (i.e., σ < 0) are referred to as sources and sinks respectively. This general equation may be used to derive any continuity equation, ranging from as simple as the volume continuity equation to as complicated as the Navier–Stokes equations. This equation also generalizes the advection equation. Other equations in physics, such as Gauss's law of the electric field and Gauss's law for gravity, have a similar mathematical form to the continuity equation, but are not usually referred to by the term "continuity equation", because j in those cases does not represent the flow of a real physical quantity. In the case that q is a conserved quantity that cannot be created or destroyed (such as energy), σ = 0 and the equations become:
Lord Nelson (1758–1805) was preserved for two months in brandy and spirits of wine mixed with camphor and myrrh after which time the body was found to be in excellent condition and completely plastic. Various communist leaders have been embalmed and put on public display. Perhaps the most famous embalmed body of the 20th century is that of Vladimir Lenin, which continues to draw crowds decades after his death in 1924, and is seen in his Moscow mausoleum. Joseph Stalin was also embalmed and placed next to Lenin, but his body was buried in 1961 during de-Stalinization. Klement Gottwald of Czechoslovakia, who died just five days after attending Stalin's funeral, was embalmed and displayed in a mausoleum at National Monument in Vitkov in Prague. However, in 1962 due to political reasons, the body was removed and cremated. Bulgarian Georgi Dimitrov was embalmed and placed on display in the Sofia Georgi Dimitrov Mausoleum. After the fall of Communism in Bulgaria, his body was buried in 1990 in the Central cemetery of Sofia. Mongolia's Khorloogiin Choibalsan, Angola's Agostinho Neto, Romania's Gheorghe Gheorghiu-Dej and Guyana's Forbes Burnham were also embalmed by the same Russian team. Currently, embalmed communist leaders can also be found in the Mausoleum of Mao Zedong, the Ho Chi Minh Mausoleum, and the Kumsusan Palace of the Sun for Kim Il Sung and Kim Jong Il.
Sources: en.wikipedia.org
It is a synthetic peptide of seven amino acids. Its backbone corresponds to a fragment of adrenocorticotropic hormone extended at the carboxyl end. The material is distributed as a lyophilized solid for laboratory use.
The extension was introduced to slow enzymatic breakdown of the peptide in biological systems. Natural ACTH fragments are degraded rapidly by peptidases. Adding the tripeptide was intended to extend the window during which the molecule remains intact.
Most published work consists of animal experiments conducted in a small number of laboratories. Human data are limited in number and size. Whether the observed effects translate into reliable clinical benefit is still unresolved.
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.