Heptapeptide is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2025-08-19. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Free acid form of the heptapeptide; depends on terminal groups |
| Molecular mass | About 813.9 g/mol | Average mass used for mass spectrometry confirmation |
| Appearance | White to off-white solid | Supplied as a lyophilised powder; hygroscopic |
| Solubility class | Freely soluble in aqueous media | Water, saline, and phosphate buffers; limited organic solubility |
| Typical storage temperature | -20 degrees Celsius | Long term and dry; short working periods may use 2 to 8 degrees Celsius |
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 legion was probably founded by Diocletian to help defend the Danube. I Pontica: the legion was founded by Dioceltian to help defend Pontus Polemoniacus. The legion was stationed in Trapezus. Legio II II Armeniaca II Britannica: comitatensis under Magister Peditum II Flavia Constantia: comitatensis under the command of the Magister Peditum II Flavia Virtutis: comitatensis under the command of the Magister Peditum II Herculia (devoted to Hercules): levied by Diocletian, stationed in Scythia Minor II Isaura II Iulia Alpina: pseudocomitatensis under the command of the Magister Peditum, in Comes Illyricum command. It was probably founded by Crispus or Constans. Its objective was to defend Alpes Cottiae II Felix Valentis Thebaeorum: comitatensis Legio III III Diocletiana III Flavia Salutis: comitatensis unit of the Late Roman Empire under the command of the Magister Militum in the west. The Legio III Flavia Salutis was raised by either Constantius II or Diocletian and was used to guard North Africa. III Herculea: comitatensis under the command of the Comes Illyricum III Isaura III Iulia Alpina: comitatensis under the command of the Magister Peditum command in Italy Legio IV IV Italica IV Martia IV Parthica Legio V V Iovia (maybe the Jovians) V Parthica Legio VI VI Gemella VI Gallicana VI Herculia (maybe the Herculians) VI Hispana VI Parthica Legio XII XII Victrix
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Sources: en.wikipedia.org
To treat complications, medications can be prescribed including midodrine for autonomic neuropathy, amiodarone for patients with atrial fibrillation to prevent arrhythmias, and warfarin used after a cardioembolic episode. Familial (ATTRm-CM) Treatment: In recent years there have been developments in the treatment of Familial/Transthyretin cardiac amyloidosis including methods to suppress transthyretin production, stabilize amyloid fibrils, and medications that can destroy already existing fibrils. For familial amyloidosis, ACE-inhibitors and beta-blockers can be prescribed if there is no autonomic neuropathy.
If there have not been out of tolerance temperatures for critical times, continue to use the shipment, without special inspection If potentially damaging temperature hazards have occurred, thoroughly inspect the shipment for damage or degradation. Possibly accelerate sale and use because of reduced shelf life. The consignee may negotiate with the carrier or shipper or even choose to reject a shipment where sensors indicate severe temperature history The time of the temperature extreme, or GPS tracking, may be able to determine the location of the infraction to direct appropriate corrective action. Multiple replicate shipments of data loggers are also used to compare modes of shipment (routes, vendors) and to develop composite data to be used in package testing protocols. There are many brands and models of data loggers. Most are a connectable device that must be plugged into a computer to extract the data that the logger has logged.
September 10, 2010: Canada Statistics Canada said an additional 36,000 people got jobs in August, but the unemployment rate rose 0.1 percentage points, to 8.1%, as a larger number of people sought work. That raised the number of unemployed by 17,800, to slightly more than 1.5 million. Excluding the bounce in education jobs, employment actually fell by about 32,000, economists at BMO Capital Markets and CIBC said.
Sources: en.wikipedia.org
It is described as a synthetic analogue of the ACTH(4–10) fragment, a short segment of adrenocorticotropic hormone. Its sequence differs from that fragment and includes two proline residues, which influence stability and behaviour in solution.
It appears in Russian pharmaceutical listings as a nasal formulation, but it is not an authorised medicine in the United States or the European Union. Outside those markets it is normally encountered as a research chemical rather than a prescription product.
Laboratory and animal work points to melanocortin signalling and changes in neurotrophic factor levels, especially brain-derived neurotrophic factor. The exact receptor targets and the degree to which these findings transfer to humans are still unresolved.
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.