ACTH 片段 raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-07-19 and is reviewed periodically as new material appears.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
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。
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。
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
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.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
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.
Tachykinin peptides are also involved in inflammation, and tachykinin receptor antagonists have been researched for use in treating inflammatory conditions such as asthma and irritable bowel syndrome. The main use for which these antagonist drugs have been applied so far, however, is as antiemetics, in both human and veterinary medicine. Examples of tachykinin antagonists include:
eggNOG GreenPhylDB for plants InParanoid focuses on pairwise ortholog relationships OHNOLOGS is a repository of the genes retained from whole genome duplications in the vertebrate genomes including human and mouse. OMA OrthoDB appreciates that the orthology concept is relative to different speciation points by providing a hierarchy of orthologs along the species tree. OrthoInspector Archived 2020-01-27 at the Wayback Machine is a repository of orthologous genes for 4753 organisms covering the three domains of life OrthologID OrthoMaM for mammals OrthoMCL Roundup SonicParanoid is a graph based method that uses machine learning to reduce execution times and infer orthologs at the domain level. Tree-based phylogenetic approaches aim to distinguish speciation from gene duplication events by comparing gene trees with species trees, as implemented in databases and software tools such as:
=== Herstatin === Herstatin is an autoinhibitor of the ErbB family, which binds to RTKs and blocks receptor dimerization and tyrosine phosphorylation. CHO cells transfected with herstatin resulted in reduced receptor oligomerization, clonal growth and receptor tyrosine phosphorylation in response to EGF.
All I can personally do, at least for now, is stuff like this." Laidlaw also contributed to Valve's puzzle series Portal, which is set in the Half-Life universe. He disliked the crossover, feeling it "made both universes smaller", and said later: "I just had to react as gracefully as I could to the fact that it was going there without me. It didn't make any sense except from a resource-restricted point of view."
Sublingual administration of medications that are subject to a high first-pass effect with oral administration can result in improved bioavailability because the first pass through the intestines and liver is bypassed. As a result, sublingual estradiol has been found to result in estradiol levels and a ratio of estradiol to estrone that are substantially higher than oral estradiol. Maximal circulating levels of estradiol are as much as 10-fold higher with sublingual administration than with oral administration, and the absolute bioavailability of estradiol is approximately 5-fold higher. On the other hand, levels of estradiol fall rapidly with sublingual administration, whereas they remain elevated for a prolonged period of time with oral administration. This is due to the large circulating pool of hormonally inert estrogen conjugates with long half-lives that is reversibly generated with oral estradiol during first-pass metabolism, which serves as a metabolism-resistant and long-lasting reservoir for continuous reconversion back into estradiol. It is also responsible for the differences in ratios between sublingual estradiol and oral estradiol in terms of maximal estradiol levels (10:1) achieved and absolute bioavailability (5:1). A study in marmoset monkeys found that the bioavailability of sublingual estradiol was 10% of that of estradiol administered by intramuscular injection. After a dose of sublingual estradiol, levels of estrone start to slowly but progressively rise within 10 minutes.
Sources: en.wikipedia.org
The government of Rodríguez Zapatero brought to parliament a series of legal reforms for the "extension of rights" to citizens, some of which met with stiff opposition from the PP and conservative sectors, especially the law recognizing same-sex marriage, the o-called" express divorce" law, the law for the effective equality of women and men or the Historical Memory Law. In the mobilizations against these reforms, various Catholic organizations and the Spanish ecclesiastical hierarchy itself played a special role. Likewise, the Catholic bishops – also the PP – opposed head-on the educational reform of the LOE promoted by the government and especially the introduction in schools of the new subject of Education for Citizenship. After many months of intense debates, the Parliament of Catalonia approved on September 30, 2005, the new Statute of Autonomy of Catalonia bill which stated in its article 1 that "Catalonia is a nation". It was immediately criticized by the PP and the media because, according to them, it meant the establishment of a new "federal" or "confederal" model of the State which openly broke with the Constitution of 1978. Voices were also raised within the PSOE against the "Statute" and against president of the Generalitat of Catalonia Pasqual Maragall, of the PSC.
=== Hair loss === Studies have reported that PRP is beneficial for alopecia areata and androgenetic alopecia and can be used as an alternative to minoxidil or finasteride. A review reported it to improve hair density and thickness in both genders. A minimum of 3 treatments, once a month for 3 months are recommended, and afterwards a 3-6 month period of continual appointments for maintenance. Factors that determine efficacy include number of sessions, double versus single centrifugation, age, gender, and the injection site.
=== Treatment process === Preliminary testing, preferably on a like textile, is essential to establish a conservation strategy that effectively stabilizes the object through minimal intervention. Treatment starts with the selection of a compatible adhesive and support substrate. The material options are the same as those used for stitching methods. Silk crepeline is popular because it is more pliable than polyester crepeline (Stabiltex), but paper can also be a suitable support depending on the object. Substrata can be dyed to match the color of the textile being consolidated. Surface preparation involves adhesive application by brush, roller, sponge, or spraying in a fume-extraction booth. The prepared substrate is then placed adhesive side down over the textile and covered with absorbent blotting paper that is pinned or weighted. Methods of affixing the adhesive support to the textile artifact include spatula or flat iron, vacuum hot table, vacuum cold-lining, solvent activation, and direct wet or semi-dry application. For instance, cellulose and starch-coated paper can be activated with steam vapor and applied to the textile through vacuum cold-lining creating a bond with the underlying material.
== Causes == Damage from mechanical stress with insufficient self-repair by joints is believed to be the primary cause of osteoarthritis. Sources of this stress may include misalignments of bones caused by congenital or pathogenic causes; mechanical injury; excess body weight; loss of strength in the muscles supporting a joint; and impairment of peripheral nerves, leading to sudden or uncoordinated movements. The risk of osteoarthritis increases with aging, history of joint injury, or family history of osteoarthritis. However exercise, including running in the absence of injury, has not been found to increase the risk of knee osteoarthritis. Nor has cracking one's knuckles been found to play a role.
Sources: en.wikipedia.org
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
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。