This is a working overview of Alpha-MSH, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-01-30. Anything still debated is marked as such rather than presented as settled.
The compound was developed in the late 1980s and early 1990s by academic researchers investigating melanocortin signaling and pigmentation. Early work explored whether synthetic analogs could reproduce effects of the natural hormone under controlled conditions. The molecule never advanced through the full regulatory pathway required for approval as a medicine. From the mid-2000s onward it appeared in unregulated consumer markets, often distributed through informal channels. That gap between research origins and commercial availability shapes how the compound is discussed today.
Melanotan-2 is a synthetic peptide designed as an analog of alpha-melanocyte-stimulating hormone, a signaling molecule produced in the pituitary and skin. Its structure is a linear chain of seven amino acids that folds into a ring through an internal lactam bridge joining two side chains. The compound is sometimes written as MT-II or MEL-2 in informal and commercial contexts. It belongs to the melanocortin peptide family, a group of short signaling molecules that share a conserved core sequence recognized by melanocortin receptors.
Two structural changes distinguish the synthetic peptide from the natural hormone. A norleucine residue replaces methionine at one position, and a D-configured phenylalanine replaces the natural L-form at another. Both substitutions slow enzymatic breakdown, which extends the molecule's persistence relative to the parent hormone. The lactam bridge further constrains the backbone into a stable conformation. These features are standard design strategies in peptide chemistry and are not unique to this compound; they appear across many research peptides built for improved stability.
Receptor-binding studies classify melanotan II as a non-selective melanocortin agonist. It interacts with MC1R, MC3R, MC4R and MC5R, with reported affinities in the low nanomolar range and no strong subtype preference. Activation of MC1R on dermal melanocytes shifts pigment synthesis toward eumelanin, the dark polymer deposited in melanosomes and transferred to keratinocytes. Because the same peptide engages MC4R in the hypothalamus, it also appears in animal work on food intake and erectile response, which is why it is discussed in both pigment and metabolic research. Which receptor populations dominate after systemic exposure in humans is not fully established.
Published pharmacokinetic information is limited and comes mainly from small studies rather than registrational trials. Plasma half-life is usually described as short, on the order of tens of minutes, followed by rapid tissue distribution and clearance of the intact peptide. Metabolites and low concentrations of parent compound have been reported in urine, a detail relevant to anti-doping and forensic testing. Whether repeated exposure changes receptor sensitivity or clearance over time remains an open question. Values differ noticeably between analytical assays, so published numbers should be read as approximate rather than definitive.
Melanotan II is a synthetic cyclic heptapeptide with the sequence Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, corresponding to a molecular formula of C50H69N15O9 and a monoisotopic mass near 1024 daltons. It was designed as a structural analogue of alpha-melanocyte-stimulating hormone, a peptide hormone produced by cleavage of proopiomelanocortin. A lactam bridge between the aspartate and lysine side chains closes the ring, and the C-terminal amide removes a free carboxyl group. Both modifications increase resistance to enzymatic degradation compared with the linear parent hormone. Four substitutions distinguish it from afamelanotide, the linear analogue studied under the name melanotan I.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic cyclic heptapeptide | Analog of alpha-MSH with an internal lactam bridge |
| Molecular weight | Approximately 1024 daltons | Free base value; salt forms differ |
| Appearance | White to off-white powder | Usually supplied as a lyophilized solid |
| Solubility | Freely soluble in water | Poorly soluble in nonpolar solvents |
| Typical storage | −20 °C, dry, protected from light | Repeated freeze-thaw cycles degrade peptides |
Regulatory treatment varies between countries. Several national medicines agencies have classified the peptide as unapproved, and customs authorities in some jurisdictions seize shipments on that basis. A few jurisdictions channel supply through prescription-only frameworks that do not list the substance by name. Because the material circulates mainly through online vendors, composition and purity are rarely verified before sale. Surveys of unapproved peptide products have reported labels that did not match measured content in a substantial fraction of samples.
Melanotan II is a synthetic cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone, a naturally occurring peptide involved in pigmentation signalling. Its structure substitutes a lactam bridge between side chains to increase stability relative to the native hormone. The compound is also known by the shorthand MT-II and by several non-proprietary synonyms used in research catalogues. It is not an approved therapeutic product in any major jurisdiction; material sold under this name is typically offered as a laboratory reagent rather than as a medicine.
Melanocortin receptors comprise five subtypes with distinct tissue distributions and functions. Melanotan-2 is described in the literature as a non-selective agonist that engages several of these subtypes, including MC1R, MC3R, MC4R, and MC5R. MC1R is the subtype most directly linked to melanin production in skin cells. Because the compound is not subtype-selective, its observed effects in experimental settings are generally attributed to activity across multiple receptor pathways rather than to a single target.
Melanotan-2 is a synthetic linear peptide built from seven amino acids arranged in a short chain. Its sequence is commonly written as Ac-Nle-Asp-His-D-Phe-Arg-Trp-Lys-NH2, which includes a modified N-terminus and an amidated C-terminus. The molecule belongs to the melanocortin family and acts as a receptor agonist. Structural features such as the D-phenylalanine residue and the Nle substitution are associated with increased stability against enzymatic degradation relative to the natural parent peptide.
Structurally, Melanotan-2 retains the core recognition motif of alpha-melanocyte-stimulating hormone while adding a lactam bridge that links two side chains and constrains the molecule into a ring. This modification lowers susceptibility to enzymatic degradation. The compound acts as an agonist at melanocortin receptors, particularly subtypes associated with melanin production. Because the same receptor family influences several physiological processes, researchers note that its activity is not confined to pigmentation alone. Receptor selectivity continues to be examined in published studies.
Melanotan-2 is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone, a naturally occurring peptide involved in pigmentation signalling. Its sequence incorporates modified residues that increase potency and extend biological activity relative to the native hormone. The compound binds receptors of the melanocortin family and is examined mainly in laboratory research. It does not occur naturally and exists only as a manufactured chemical entity produced by solid-phase synthesis.
The peptide was developed during the 1980s by researchers investigating melanocortin signalling and skin pigmentation pathways. Early work focused on analogues of alpha-melanocyte-stimulating hormone that would resist enzymatic breakdown more effectively than the parent molecule. Melanotan-2 emerged from that programme as a shortened, cyclised variant. Reports describing its synthesis and receptor activity later appeared in the scientific literature. Commercial availability grew through unregulated channels rather than through pharmaceutical approval.
The compound was developed in the late 1980s and 1990s by academic researchers investigating photoprotection. The rationale held that stimulating melanin production might reduce ultraviolet damage to skin and lower skin cancer risk. Early work examined receptor binding, pigment response, and short-term tolerability in small studies. That program did not produce an approved drug, and formal development stalled after early-phase trials. Whether induced pigmentation confers meaningful photoprotection remains an open question.
Outside regulated medicine, melanotan II circulates through online vendors as a research chemical, often marketed for tanning. Products sold this way vary widely in purity, concentration, and labeling accuracy, and independent testing has documented discrepancies. Published reports describe both pigment effects and adverse reactions, including nausea, flushing, and darkening of existing moles. Long-term safety data are sparse, and no large controlled trial has established a risk profile. Questions about cumulative effects on melanocytes remain unresolved in the literature.
Melanotan II is a synthetic peptide analog modeled on alpha-melanocyte-stimulating hormone, a naturally occurring signaling peptide involved in pigmentation. Its structure is a cyclic heptapeptide containing two non-natural substitutions, norleucine at position four and D-phenylalanine at position seven. These modifications resist enzymatic breakdown and extend the molecule's activity relative to the native hormone. The compound binds melanocortin receptors and is studied mainly as a pharmacological tool rather than a therapeutic product. It has never received approval as a medicine in any major jurisdiction.
Laser microprobe mass spectrometer Particulate matter sampler Aerosol impaction Particle size analysis Hartonen, Kari; Laitinen, Totti; Riekkola, Marja-Liisa (2011). "Current instrumentation for aerosol mass spectrometry". TrAC Trends in Analytical Chemistry. 30 (9): 1486–1496. doi:10.1016/j.trac.2011.06.007. ISSN 0165-9936. Centre for Atmospheric Science TOF-AMS resources Q-AMS resources List of publications using all versions of the AMS Glossary of AMS terms
=== Radiation shielding === Depleted uranium is the best radiation shielding by weight, due to the high atomic weight of the uranium atoms; materials are more able to block radioactivity the higher their atomic weight, and uranium is one of the heaviest natural elements. Lead, the heaviest stable element, is the most common low-cost alternative, but a lead shield needs to be about three times as thick as a DU shield to provide the equivalent protection. Uranium also has by far a higher melting point 2,070 °F (1,130 °C), and its tensile strength is similar to that of steel. Industrial radiography cameras include a very high activity gamma radiation source (typically Ir-192 with an activity above 10 TBq). Depleted uranium is often used in the cameras as a shield to protect individuals from the gamma source. Typically, the uranium shield is supported and enclosed in polyurethane foam for thermal, mechanical and oxidation protection.
There are many physiological mechanisms that control starting and stopping a meal. The control of food intake is a physiologically complex, motivated behavioral system. Hormones such as cholecystokinin, bombesin, neurotensin, anorectin, calcitonin, enterostatin, leptin and corticotropin-releasing hormone have all been shown to suppress food intake. Eating rapidly leads to obesity and overeating, probably because the feelings of satiety can be slower.
== Type == The Prima Porta-type of statues of Augustus, of which Augustus of Prima Porta is the most famous example, became the prevailing representational style for him. This type was introduced around 27 BC to visually express the title Augustus and was copied full-length and in busts in various versions throughout the empire up until his death in AD 14. The copies never showed Augustus looking older, however, but represented him as forever young, in line with the aims of his propaganda, i.e. to display the authority of the Roman emperors through conventional styles and stories of the culture. At its best, in Roland R. R. Smith's view, this "type achieves a sort [of] visual paradox that might be described as mature, ageless, and authoritative youthfulness".
Sources: en.wikipedia.org
Depending on the venue's climate, the turf used was either a hybrid of 84% Kentucky bluegrass and 16% perennial ryegrass (for cooler temperatures), or Bermuda grass (for warmer temperatures). Four venues (Atlanta, Dallas, Houston, and Vancouver) were indoor stadiums that used retractable roof systems, all equipped with climate control, while a fifth, SoFi Stadium in Los Angeles, was open-air but had a translucent roof and no climate control. The host of the final match—MetLife Stadium in East Rutherford, New Jersey—was announced by FIFA on February 4, 2024. Although there were soccer-specific stadiums in Canada and the United States, the largest soccer-specific stadium in the U.S., Geodis Park in Nashville, Tennessee, seated 30,000, fell short of FIFA's minimum requirement of 40,000 seats (Toronto's BMO Field was expanded from 30,000 to 45,500 for this tournament). Stadiums including Mercedes-Benz Stadium in Atlanta; Gillette Stadium in Foxborough, Massachusetts; and Lumen Field in Seattle have been used by both National Football League (NFL) and Major League Soccer (MLS) teams. Although the Canadian and American stadiums were primarily used for gridiron football, they were also designed to accommodate soccer matches. Mexico City was the only capital of the three host nations chosen as a venue site; Ottawa and Washington, D.C., joined Bonn (West Germany, 1974) and Tokyo (Japan, 2002) as the only capital cities not selected to host World Cup matches.
=== 2-D gel electrophoresis and western blotting === Two-dimensional gel electrophoresis (2-D gel) techniques in culmination with western blotting has been used for many years in the identification of immune response magnitude. This can be accomplished by comparing various samples against molecular-weight size markers for qualitative analysis and against known amounts of protein standards for quantitative analysis.
=== Legal status === Risperidone was approved by the United States Food and Drug Administration (FDA) in 1993 for the treatment of schizophrenia. In 2003, the FDA approved risperidone for the short-term treatment of the mixed and manic states associated with bipolar disorder. In 2006, the FDA approved risperidone for the treatment of irritability in autistic children and adolescents. The FDA's decision was based in part on a study of autistic people with severe and enduring problems of violent meltdowns, aggression, and self-injury; risperidone is not recommended for autistic people with mild aggression and explosive behavior without an enduring pattern. On 22 August 2007, risperidone was approved as the only drug agent available for the treatment of schizophrenia in youths, ages 13–17; it was also approved that same day for the treatment of bipolar disorder in youths, ages 10–17, joining lithium. In December 2021, the Committee for Medicinal Products for Human Use of the European Medicines Agency recommended market authorization for Okedi, a long-acting depot injection of risperidone. Okedi was approved for the treatment of schizophrenia in adults for whom the tolerability and effectiveness of risperidone had already been established using an oral formulation. Long-acting depot injectable risperidone was approved for medical use in the European Union in February 2022.
=== February === 9 February – The Scottish Prison Service concludes its review of accommodating transgender prisoners, and recommends that transgender prisoners initially be accommodated according to their sex at birth while an individual assessment is carried out. 10 February – Following a legal challenge by lap dance performers and club owners, a ban on lap dancing clubs in Edinburgh, scheduled to come into force in April, is overturned by Edinburgh's Court of Session after it finds Edinburgh City Council acted illegally by voting to limit the number of sexual entertainment venues in the city from four to zero. 15 February – Nicola Sturgeon announces her resignation as First Minister of Scotland and Leader of the Scottish National Party after eight years in the role; she will stay on until her successor has been elected. 16 February – Deputy First Minister John Swinney rules himself out of the SNP leadership contest. 17 February – The Royal College of Nursing recommends its members accept a new pay offer of 6.5%. The offer from the Scottish Government also includes changes to conditions. 19 February Scottish Health Secretary Humza Yousaf and former Minister for Community Safety Ash Regan become the first two candidates to announce they will stand in the Scottish National Party leadership election. Keith Brown, the SNP's depute leader, Neil Gray, the Minister for International Development, and Màiri McAllan, the Environment Minister, all rule themselves out of the contest.
== Early life and education == Born in Aarberg, Switzerland, Wüthrich was educated in chemistry, physics, and mathematics at the University of Bern before pursuing his PhD supervised by Silvio Fallab at the University of Basel, awarded in 1964.
Sources: en.wikipedia.org
The Moon race is often analyzed as a microcosm of the Space Race's broader dynamics. Historians such as Jennifer Frost argue that if the Space Race is measured in terms of overall spaceflight capability, the Soviet Union "won it hands down." Asif A. Siddiqi, a noted space historian, provides a more nuanced view, emphasizing the Soviet Union's dominance in smaller aspects of the race to the moon, yet critical, benchmarks such as the first lunar impact, first photos of the Moon's far side, first soft lunar landing, and first lunar orbit. These accomplishments laid the groundwork for lunar exploration, though they are often overshadowed by the Apollo 11 mission. After the period of détente, the Soviet Union managed to send 18 crafts to Venus. However, this did not generate wide speculation from the western world.Before that landing [Apollo 11], there was an enormous amount of investment in the robotic exploration of the Moon, both by the Soviets and the US, in terms of all sorts of smaller benchmarks like the first lunar impact, the first pictures of the far side of the Moon, the first soft lunar landing, and the first lunar orbit. We forget, but in those little races, the Soviet Union dominated almost every benchmark, but it is forgotten as the United States won the big one.
The Shalwar kameez is Pakistan's national dress, worn in all provinces: Punjab, Sindh, Balochistan, Khyber Pakhtunkhwa, and Azad Kashmir. Each province has its own style. Pakistanis wear a variety of fabrics like silk, chiffon, and cotton. In addition to the national dress, men often wear domestically tailored suits and neckties, especially in offices, schools, and social gatherings. Pakistan's fashion industry has thrived, blending traditional and modern styles to create a unique cultural identity. Regional and traditional dress remain significant symbols of native tradition, evolving into both modern and purer forms. Organisations like the Pakistan Fashion Design Council in Lahore and the Fashion Pakistan Council in Karachi host events like PFDC Fashion Week and Fashion Pakistan Week. Pakistan's inaugural fashion week took place in November 2009.
=== Societies and administration === The International Union of Basic and Clinical Pharmacology, Federation of European Pharmacological Societies, and European Association for Clinical Pharmacology and Therapeutics are organizations representing standardization and regulation of clinical and scientific pharmacology. Systems for medical classification of drugs with pharmaceutical codes have been developed. These include the National Drug Code (NDC), administered by Food and Drug Administration; Drug Identification Number (DIN), administered by Health Canada under the Food and Drugs Act; Hong Kong Drug Registration, administered by the Pharmaceutical Service of the Department of Health (Hong Kong), and National Pharmaceutical Product Index in South Africa. Hierarchical systems have also been developed, including the Anatomical Therapeutic Chemical Classification System (AT, or ATC/DDD), administered by World Health Organization; Generic Product Identifier, a hierarchical classification number published by MediSpan and SNOMED, C axis. Ingredients of drugs have been categorized by Unique Ingredient Identifiers.
== Synthetic methods == Traditional polymers are usually consist of one repeating unit or several repeating units, arranged in random sequences. Sequence-controlled polymers are composed of different repeating units, which are arranged in an ordered manner. In order to control the sequence, various kinds of synthetic methodologies are developed.
== Clinical significance == Anti-endomysial antibodies (EMA) are present in celiac disease. They do not cause any direct symptoms to muscles, but detection of EMA is useful in the diagnosis of the disease.
Sources: en.wikipedia.org
It is a synthetic seven-amino-acid peptide modeled on alpha-melanocyte-stimulating hormone. It carries two non-natural substitutions and a cyclic bridge that increase its stability relative to the natural hormone. It circulates as a research chemical and is not an approved medicine.
Melanotan-1, also called afamelanotide, is a shorter linear analog with a different amino acid sequence and no lactam ring. It has been evaluated in formal clinical programs, while melanotan-2 has not. The two are distinct molecules and are not interchangeable.
No. Bremelanotide is a related but distinct cyclic peptide that reached approved status for one specific clinical indication. Melanotan-2 is a separate molecule with its own sequence and properties. Shared ancestry in the melanocortin family does not make them the same substance.
No. It is a synthetic analogue carrying four amino acid changes, a lactam ring and an amidated C-terminus. The natural hormone is a linear thirteen-amino-acid peptide processed from proopiomelanocortin.