heptapeptide comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-07-16. Where a claim depends on a specific study, the study is described rather than over-claimed.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
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。
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.
== History == The glucose clamp technique was developed by University of Texas (UT) School of Medicine Professors DeFronzo, Andres and Tobin in 1979. It has since been the gold standard for pharmacodynamic studies in diabetes drug development and diagnostics evaluation. In human clinical trials, manual glucose clamps as well as the more modern method of automated glucose clamp find common use.
== History == Ribosome profiling is based on the discovery that the mRNA within a ribosome can be isolated through the use of nucleases that degrade unprotected mRNA regions. This technique analyzes the regions of mRNAs being converted to protein, as well as the levels of translation of each region to provide insight into global gene expression. Prior to its development, efforts to measure translation in vivo included microarray analysis on the RNA isolated from polysomes, as well as translational profiling through the affinity purification of epitope tagged ribosomes. These are useful and complementary methods, but neither allows the sensitivity and positional information provided by ribosome profiling.
=== Third representation === Given uncontrolled flow rate or varied solvent composition, another representation was designed such that a different heating source and control system would allow for partial vaporization. Two different heating methods were combined because one is capable of more rapid response time while the other is slower. This combination allows the third representation of vaporizer to handle fluctuations in flow rate coming of the LC column.
== Biological role == Substrate proteins attached to cell walls by sortases include enzymes, pilins, and adhesion-mediating large surface glycoproteins. These proteins often play important roles in virulence, infection, and colonization by pathogens. Surface proteins not only promote interaction between the invading pathogen and animal tissues, but also provide ingenious strategies for bacterial escape from the host's immune response. In the case of S. aureus protein A, immunoglobulins are captured on the microbial surface and camouflage bacteria during the invasion of host tissues. S. aureus mutants lacking the srtA gene fail to anchor and display some surface proteins and are impaired in the ability to cause animal infections. Sortase acts on surface proteins that are initiated into the secretion (Sec) pathway and have their signal peptide removed by signal peptidase. The S. aureus genome encodes two sets of sortase and secretion genes. It is conceivable that S. aureus has evolved more than one pathway for the transport of 20 surface proteins to the cell wall envelope. Note that exosortase and archaeosortase are functionally analogous, while not in any way homologous to sortase.
Sources: en.wikipedia.org
== Contraindications == Acute intermittent porphyria, hypersensitivity to any barbiturate, prior dependence on barbiturates, severe respiratory insufficiency (as with chronic obstructive pulmonary disease), severe liver failure, pregnancy, and breastfeeding are contraindications for phenobarbital use.
Extended breastfeeding usually means breastfeeding beyond the age of 12 to 24 months, depending on the culture. The American Academy of Family Physicians states that "health outcomes for mothers and babies are best when breastfeeding continues for at least two years. The American Academy of Pediatrics recommends that mothers nurse for the first 12 months and "thereafter for as long as mother and baby desire." The World Health Organization recommends breastfeeding up to age 2 "or beyond." Breast milk is known to contain lactoferrin (Lf), which protects the infant from infection caused by a wide range of pathogens. The amount of Lf in breast milk is lactation-stage related. One study evaluated Lf concentration in prolonged lactation from the first to the 48th month postpartum. It was found to be at the highest level in colostrum, dropped to the lowest level during 1 – 12 months of lactation, and then increased significantly during the 13–24 months of lactation, close to the Lf concentration in colostrum. At over 24 months, the level dropped, though not significantly.
==== Cognitive behavioral therapy ==== Cognitive behavioral therapy (CBT) is useful in adolescents and adults with anorexia nervosa. One of the most known psychotherapy in the field is CBT-E, an enhanced cognitive-behavior therapy specifically focus to eating disorder psychopathology. Acceptance and commitment therapy is a third-wave cognitive-behavioral therapy which has shown promise in the treatment of AN. Cognitive remediation therapy (CRT) is also used in treating anorexia nervosa. Schema-Focused Therapy (a form of CBT) was developed by Dr. Jeffrey Young and is effective in helping patients identify origins and triggers for disordered eating.
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.