A practical reference on Melanocortin receptor: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-09-26 and is reviewed periodically as new material appears.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White lyophilized powder | Typical for synthetic peptides |
| Solubility | Freely soluble in water | Also soluble in saline |
| Storage temperature | -20 C or below | Protect from repeated freeze-thaw |
| Analytical method | Reverse-phase HPLC | Confirms purity and identity |
| Common synonym | ACTH(4-10) analog | Reflects structural origin |
从分子层面看，Semax 是线性七肽，没有二硫键、糖基或脂链修饰，N 端为游离氨基，C 端为游离羧基。分子含组氨酸与谷氨酸侧链，因此在水和甲醇等极性溶剂中溶解良好，在非极性溶剂中溶解有限。计算分子量约为 814 Da，与其质子化离子的质荷比吻合，可用于质谱确认。
稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定，遇到强碱或长时间高温则明显断裂；甲硫氨酸侧链容易被氧化成亚砜，使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间，配制后的水溶液通常需要冷藏并尽快用完。
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
=== Cardiovascular === MMP9 levels increase with the progression of idiopathic atrial fibrillation. MMP9 has been found to be associated with the development of aortic aneurysms, and its disruption prevents the development of aortic aneurysms. Doxycycline suppresses the growth of aortic aneurysms in animal models through its inhibition of MMP9 reduces aortic inflammation in humans.
As it gained popularity, opium, and after 1820, morphine, was mixed with a wide variety of agents, drugs and chemicals including mercury, hashish, cayenne pepper, ether, chloroform, belladonna, whiskey, wine and brandy."
This use a treatment for disease was pioneered in 1890 by Emil von Behring and Shibasaburo Kitasato, who first demonstrated that the endotoxin from the infectious diseases diphtheria and tetanus could be used to prevent or cure non-immunized animals using serum transfusions from an immune animal to a susceptible one. Building on in this logic, and at the same session of the Society of Biology in Paris on February 10, 1894, Albert Calmette at the Pasteur Institute and independently Césaire Phisalix and Gabriel Bertrand at the Department of Pathology and Chemistry in the National Museum of National History in France, announced that they had achieved treatment of a vulnerable animal with serum from an immunized one both using snake venom. Calmette went on subsequently to immunize horses using venom from Indian cobras, and the resulting Serum Antivenimeux (antivenomous serum) became the first commercially available antivenom product. In 1895 Sir Thomas Fraser, Professor of Medicine at the University of Edinburgh, also produced a serum to act against cobra venom. His "antivenene" was effective in the laboratory. In 1901, Vital Brazil, working at the Instituto Butantan in São Paulo, Brazil, developed the first monovalent and polyvalent antivenoms for Central and South American Crotalus and Bothrops snakes, as well as for certain species of venomous spiders, scorpions, and frogs. In Mexico in 1905, Daniel Vergara Lope developed an antivenom against scorpion venom, by immunizing dogs. In Australia, the Commonwealth Serum Laboratories (CSL) began antivenom research in the 1920s.
Andrés de Santa Cruz, who would have had apparent contradictions in his geopolitical projects, due to a highland nationalism, in which he wanted both the reunification of Upper and Lower Peru (in a similar way to the Inca Empire or the Viceroyalty of Peru) as well as to consider dividing Peru into 2 states, one from the north and the other from the south, for the benefit of Bolivia's interests (in addition to recovering the territory of Arica for the benefit of Bolivia), which he envisioned as the "Macedonia of America" and which should have a leadership in the continent, to the detriment of the historical preponderance of Lima and Cuzco as poles of power."When he felt strong, his dreams of power were those of those legendary Incas who descended from the mountains to bring peace, order, and progress to the coast. Then he opened himself to the ideal of 'pan-Peru', of Greater Peru. Bolivia would be the "Macedonia of America". If they beat and humiliated him and cornered him on the plateau, he wanted, not so much for revenge as for security reasons, next to Bolivia, a divided or impotent Peru. His maximum program was a strong Greater Peru and extensive, that is, the Confederation, with him as head. His minimum program was to govern Bolivia, but, at his side, the bifurcation of Peru into two states and the possible fall of the South State under Bolivia's sphere of influence Such is the explanation of his political behavior until 1839.
Sources: en.wikipedia.org
=== Combined & global === A different modality is when lysosomes do not just act alone, but in concert with the ER. In this scenario, lysosomes first supply a local, 'trigger' Ca2+ release that then secondarily recruits the IP3Rs or RyRs on the ER by Calcium-induced calcium release (the 'amplifier'). In this mode, lysosomes indirectly evoke a global cytosolic Ca2+ signal (which is actually mediated by the ER). In this way, lysosomal Ca2+ release is amplified, in what is referred to as the 'trigger hypothesis'.
=== Transmission === Smallpox was highly contagious, but generally spread more slowly and less widely than some other viral diseases, perhaps because transmission required close contact and occurred after the onset of the rash. The overall rate of infection was also affected by the short duration of the infectious stage. In temperate areas, the number of smallpox infections was highest during the winter and spring. In tropical areas, seasonal variation was less evident and the disease was present throughout the year. Age distribution of smallpox infections depended on acquired immunity. Vaccination immunity declined over time and was probably lost within thirty years. Smallpox was not known to be transmitted by insects or animals and there was no asymptomatic carrier state. Transmission occurred through inhalation of airborne variola virus, usually droplets expressed from the oral, nasal, or pharyngeal mucosa of an infected person. It was transmitted from one person to another primarily through prolonged face-to-face contact with an infected person. Some infections of laundry workers with smallpox after handling contaminated bedding suggested that smallpox could be spread through direct contact with contaminated objects (fomites), but this was found to be rare. Also rarely, smallpox was spread by virus carried in the air in enclosed settings such as buildings, buses, and trains. The virus can cross the placenta, but the incidence of congenital smallpox was relatively low.
== History == Glucose was first isolated from raisins in 1747 by the German chemist Andreas Marggraf. Glucose was discovered in grapes by another German chemist, Johann Tobias Lowitz, in 1792, and distinguished as being different from cane sugar (sucrose). Glucose is the term coined by Jean-Baptiste Dumas in 1838, which has prevailed in the chemical literature. Friedrich August Kekulé proposed the term dextrose (from the Latin dexter, meaning "right"), because in aqueous solutions of glucose, the plane of linearly polarized light is turned to the right. In contrast, l-fructose (usually referred to as l-fructose) (a ketohexose) and l-glucose (l-glucose) turn linearly polarized light to the left. The earlier notation according to the rotation of the plane of linearly polarized light (d and l-nomenclature) was later abandoned in favor of the d- and l-notation, which refers to the absolute configuration of the asymmetric center furthest from the carbonyl group, and in concordance with the configuration of d- or l-glyceraldehyde. Since glucose is a basic necessity of many organisms, a correct understanding of its chemical makeup and structure contributed greatly to a general advancement in organic chemistry. This understanding occurred largely as a result of the investigations of Hermann Emil Fischer, a German chemist who received the 1902 Nobel Prize in Chemistry for his findings.
Sources: en.wikipedia.org
It is associated with the melanocortin receptor family, particularly subtypes found in the central nervous system. This interaction is separate from the adrenal pathway activated by full-length ACTH.
Peptidases degrade the compound within minutes in circulation. This short half-life is one reason nasal delivery is used, placing the substance close to the olfactory and trigeminal pathways.
No large multicenter trials have been published in English-language journals. The existing human evidence consists mainly of smaller studies conducted in Russia, which limits generalization.
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.