This is a working overview of ACTH(4-10), written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-02-28 and is reviewed periodically as new material appears.
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.
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。
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。
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analogue of the ACTH(4-10) fragment |
| Amino acid sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Single-letter form MEHFPGP |
| Molecular formula | C37H51N9O10S | Free peptide, nominal mass near 814 Da |
| First registration | 1994, Russia | Nasal formulation for neurological indications |
| Typical purity grade | 95% or higher by HPLC | Research material; higher grades used as reference standards |
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
Published research covers ischemic stroke, traumatic brain injury, cognitive impairment, optic nerve conditions and attention-related measures. Much of the human evidence comes from small trials conducted in one country, which limits how far the results generalize. Animal models supply the larger share of the data, and effects seen in rodents do not transfer automatically to people. Reviews have noted that methodological reporting is often incomplete, making it difficult to pool results or compare treatment schedules across studies.
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.
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.
Hydrostatic CCC or centrifugal partition chromatography (CPC) was invented in the 1980s by the Japanese company Sanki Engineering Ltd, whose president was Kanichi Nunogaki. CPC has been extensively developed in France starting from the late 1990s. In France, they initially optimized the stacked disc concept initiated by Sanki. More recently, in France and UK, non-stacked disc CPC configurations have been developed with PTFE, stainless steel or titanium rotors. These have been designed to overcome possible leakages between the stacked discs of the original concept, and to allow steam cleaning for good manufacturing practice. The volumes ranging from a 100 ml to 12 liters are available in different rotor materials. The 25-liter rotor CPC has a titanium rotor. This technique is sometimes sold under the name "fast" CPC or "high-performance" CPC.
Tuberculin/PPD is injected into the skin for the tuberculin skin test. After some time the amount of swelling is measured to determine the immune system's current level of activity against tuberculosis. A high level of swelling is considered proof for tuberculosis infection. The currently globally accepted method is the Mantoux test, named after French physician Charles Mantoux who pioneered using such a test in 1907. However, this test was not reliable enough until the replacement of crude tuberculin by PPD in the 1940s. In the Mantoux test, the swelling is measured after 48 to 72 hours. If the area has a diameter more than a five to ten millimeters of swelling, the test is considered positive. Reliable administration of the skin test requires large amounts of training, supervision, and practice. The test may be falsely positive in those who have been previously vaccinated with BCG or have been infected by other types of mycobacteria. The test may be falsely negative within ten weeks of infection, in those less than six months old, and in those who have been infected for many years. Alternative skin test methods include:
Promethium is a generally synthetic chemical element; it has symbol Pm and atomic number 61. All of its isotopes are radioactive; it is extremely rare, with only about 500–600 grams naturally occurring in the Earth's crust at any given time. Promethium is one of only two radioactive elements that are both preceded and succeeded in the periodic table by elements with stable forms, the other being technetium. Chemically, promethium is a lanthanide. Promethium shows only one stable oxidation state of +3. In 1902 Bohuslav Brauner suggested that there was a then-unknown element with properties intermediate between those of the known elements neodymium (60) and samarium (62); this was confirmed in 1914 by Henry Moseley, who, having measured the atomic numbers of all the elements then known, found that the element with atomic number 61 was missing. In 1926, two groups (one Italian and one American) claimed to have isolated a sample of element 61; both "discoveries" were soon proven to be false. In 1938, during a nuclear experiment conducted at Ohio State University, a few radioactive nuclides were produced that certainly were not radioisotopes of neodymium or samarium, but there was a lack of chemical proof that element 61 was produced, and the discovery was not much recognized. Promethium was first produced and characterized at Oak Ridge National Laboratory in 1945 by the separation and analysis of the fission products of uranium fuel irradiated in a graphite reactor.
Chlorpropamide and other sulfonylureas encourage weight gain, so they are generally not favored for use in very obese patients. Metformin (Glucophage) is considered a better drug for these patients. Sulfonylureas should be used with caution or generally avoided in patients with hepatic and renal impairment, patients with porphyria, patients who are breastfeeding, patients with ketoacidosis, and elderly patients.
The majority of π-helices are only 7 residues in length and do adopt regularly repeating (φ, ψ) dihedral angles throughout the entire structure like that of α-helices or β-sheets. Because of this, textbooks that provide single dihedral values for all residues in the π-helix are misleading. Some generalizations can be made, however. When the first and last residue pairs are excluded, dihedral angles exist such that the ψ dihedral angle of one residue and the φ dihedral angle of the next residue sum to roughly −125°. The first and last residue pairs sum to −95° and −105°, respectively. For comparison, the sum of the dihedral angles for a 310 helix is roughly −75°, whereas that for the α-helix is roughly −105°. Proline is often seen immediately following the end of π-helices. The general formula for the rotation angle Ω per residue of any polypeptide helix with trans isomers is given by the equation
Sources: en.wikipedia.org
Beginning in the 2000s, many countries introduced e-visas and electronic travel authorisations (ETAs) as an alternative to traditional visas. An ETA is a form of pre-arrival registration, which may or may not be officially classified as a visa depending on the issuing jurisdiction, and is required for foreign travellers who are exempt from obtaining a full visa. In contrast to the procedures that typically apply regarding proper visas, under which the traveller normally has no recourse if rejected, if an ETA is rejected, the traveller can choose to apply for a visa instead. In contrast, an e-visa is a visa that travellers can apply for and obtain online, without visiting the issuing state's consular mission or visa agency. The following jurisdictions require certain categories of international travellers to hold an ETA or e-visa to clear border controls upon arrival:
=== Todd Barber === Todd Barber (Branden Cook) is Harper's ex-boyfriend from New York. The two remain sexually involved after their breakup, and he helps her forge her university transcripts when she is hired to Pierpoint. Todd later visits Harper in London; the two have a fight after Harper discovers he stole an expensive jacket from a patron at the nightclub they went to, where Todd calls Harper a coward and a hypocrite. Harper cuts ties with him for good.
The tubers have a crunchy texture and a sweet, nutty flavour. They can be eaten raw, pickled, dried or cooked. A wide range of uses for this vegetable leads to various dishes in the cuisine of many countries. They can be prepared similarly to Jerusalem artichokes. The leaves can be dried and made into a tea. In Chinese and Japanese cuisine, S. affinis is primarily pickled. In particular, its tuber is a part of Osechi, cooked for celebrating Japanese New Year. Dyed red by leaves of Perilla (red shiso) after being pickled, it is called chorogi. In Korea it is called choseokjam (초석잠). In French cuisine, its cooked tuber is often served alongside dishes named japonaise or Japanese-styled.
==== Formation of the neurotransmitter gamma-aminobutyric acid ==== A study conducted on the GABAergic neurons (i.e., nerve cells) in the neocortex of rat brains reported that the cytosolic form of the aspartate transaminase enzyme metabolizes α-ketoglutarate to glutamate which in turn is metabolized by glutamic acid decarboxylase to the inhibitory neurotransmitter gamma-aminobutyric acid. These metabolic reactions occur at the ends of the inhibitory axons of the GABAergic neurons and result in the release of gamma-aminobutyric acid which then inhibits the activation of nearby neurons.
Sources: en.wikipedia.org
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.
No. The peptide is synthetic, although it is modelled on a fragment of a naturally occurring hormone. ACTH(4-10) is generated when ACTH is cleaved, but the Pro-Gly-Pro extension is not a known endogenous sequence. It is therefore a designed analogue rather than a natural metabolite.
The label reflects reported effects on attention, memory and recovery after neurological injury in regional clinical reports. Those reports are mostly small and have not been widely replicated outside the region. The classification is descriptive and does not imply a single defined mechanism.
电喷雾或基质辅助激光解吸电离质谱是常用手段，测得的质子化离子质荷比可换算为分子量。结果与理论值落在合理误差内，才支持结构一致的判断。