This is a working overview of alpha-MSH analog, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-12-05 and is reviewed periodically as new material appears.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, which separates the target peptide from truncated or oxidised impurities. Mass spectrometry, most often coupled to liquid chromatography, confirms molecular mass and detects substitutions that chromatography alone may miss. Amino acid analysis and peptide mapping supply additional structural evidence, while nuclear magnetic resonance is reserved for full structural confirmation. Laboratories that examine samples sold online report wide variation in actual content, with some vials containing little or none of the labelled material.
Melanotan-2 appears on the World Anti-Doping Agency prohibited list within the peptide hormone class, and several national regulators treat it as an unapproved prescription substance. Some countries restrict importation or sale for personal use. Because the compound is widely traded as a research chemical, the practical legal picture differs between jurisdictions and shifts over time. Human safety data covering long periods are limited, and whether repeated pigmentation changes carry any lasting risk to melanocytes remains an open question.
Research interest has centred on photoprotection and pigmentation, with a smaller body of work on appetite and sexual function. Published human data remain limited to small, frequently uncontrolled studies, and the compound has never received marketing approval from a national medicines regulator. Most laboratory work treats it as a pharmacological tool for probing melanocortin signalling in cell culture or animal models. Whether pigmentation changes observed in people translate into measurable protection against ultraviolet-induced DNA damage remains an open question.
Melanotan-2 is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone, the naturally occurring peptide involved in pigmentation signalling. Its sequence is conventionally written as Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, with a lactam bridge joining the aspartate side chain to the lysine side chain. The empirical formula is C50H69N15O9 and the monoisotopic mass lies near 1023.5 daltons. N-terminal acetylation and the D-configured phenylalanine both increase resistance to enzymatic breakdown compared with the parent hormone.
| Property | Value | Notes |
|---|---|---|
| Typical storage temperature | -20 °C or below | For the lyophilised powder, desiccated |
| Storage form | Sealed vial, protected from light | Amber glass or foil-wrapped containers |
| Reconstituted stability | Short, refrigerate | Degradation accelerates in solution |
| Typical analytical method | Reversed-phase HPLC with mass spectrometry | Purity assessment plus identity confirmation |
| Common synonyms | Melanotan II, MT-II | Also written melanotan-2 |
Regulatory treatment varies by country. In the United States the peptide is not approved as a medicine, and products offered for human use may be treated as unapproved new drugs; some states also restrict sale. Australia, the United Kingdom, and European Union member states apply comparable restrictions to unapproved peptide products. Border agencies have seized shipments labelled as research chemicals. Classification may change over time, and the legal position for personal importation is not clearly settled in most published guidance.
Lyophilised melanotan-2 is supplied as a solid, which is more stable than a solution. The material is hygroscopic, so weighing is done quickly, in low humidity, with the container kept sealed. Reconstitution usually uses water for injection or bacteriostatic water, added down the wall of the vial to limit foaming. A reconstituted solution is held at 2 to 8 °C and kept away from light. Repeated freezing and thawing of the same vial is avoided because ice crystal formation and concentration effects degrade the peptide.
Published human data come mostly from small, short studies rather than large controlled trials. Reported outcomes include increased skin pigmentation and, in some reports, effects on appetite and libido, but sample sizes are small and follow-up is limited. Whether long-term use produces durable pigment changes or adverse effects is not established. Because products sold outside pharmacies are not standardized, the actual content of any given vial is often unknown. Independent testing of such material is uncommon.
Melanotan II is a synthetic cyclic heptapeptide analog derived from the core sequence of alpha-melanocyte-stimulating hormone. Researchers at the University of Arizona synthesized it during the 1980s while studying pigmentation and appetite signaling. The compound is not an approved medicine in any major jurisdiction and appears mainly in laboratory and research-chemical settings. Its structure incorporates a lactam bridge between side chains, which constrains the ring and slows enzymatic breakdown relative to the natural hormone.
Melanotan II binds several melanocortin receptor subtypes rather than a single target. MC1R on melanocytes drives melanin synthesis, while MC3R and MC4R participate in energy balance, appetite, and sexual response pathways. This lack of selectivity explains why reported effects extend beyond skin darkening. Substitutions at positions four and seven, including norleucine and D-phenylalanine, increase potency and resistance to peptidases. Understanding which receptor mediates which effect remains an active area of investigation.
Published research on the compound remains limited. Much of the human data comes from small, early-stage studies rather than large controlled trials, and several questions about effects and variability between individuals remain open. Investigators have examined receptor activity, pigment pathways, and related physiological responses in laboratory and animal models. Findings from those models do not automatically translate to human outcomes. Reviews frequently note the scarcity of rigorous clinical evidence and call for better-characterized study material.
Because the substance circulates mainly through informal markets, verification is a recurring theme in technical discussion. Independent analyses have found that labeled content and actual content can diverge, and that purity varies between samples. Analytical laboratories use reversed-phase chromatography to separate components and mass spectrometry to confirm identity. Isotope-labeled internal standards improve quantification in complex matrices. Such methods describe what a sample contains but say nothing about its sterility, lawful status, or suitability for any use. Open questions remain about how consistently testing is applied across the supply chain.
Regulatory treatment of this peptide varies by country. It holds no marketing authorization as a medicine in the United States, the European Union, or most other jurisdictions. Some countries classify products containing it as prescription-only or unlicensed medicines, which restricts lawful supply. Authorities have issued public notices warning that unregulated products may contain undeclared or incorrect ingredients. The molecule also appears on prohibited lists for competitive sport. These measures address supply oversight rather than any approved therapeutic role.
When a patient develops a simultaneous direct and indirect hernia on the same side, it is called a pantaloon hernia or saddlebag hernia because it resembles a pair of pants with the epigastric vessels in the crotch, and the defects can be repaired separately or together. Another term for pantaloon hernia is Romberg's hernia. Since the abdominal walls weaken with age, direct hernias tend to occur in the middle-aged and elderly. This is in contrast to indirect hernias, which can occur at any age, including the young, since their etiology includes a congenital component where the inguinal canal is left more patent (compared to individuals less susceptible to indirect hernias). Additional risk factors include chronic constipation, being overweight or obese, chronic cough, family history and prior episodes of direct inguinal hernias.
Consistent with KOR induced negative affective states and role in drug addiction, KOR antagonists are efficacious at blocking negative affect induced by drug withdrawal and at decreasing escalated drug intake in pre-clinical trial involving extended drug access. Traditional models of KOR function in drug addiction have postulated that KOR signaling is associated with dysphoria and aversion, thought to underlie the stress-induced exacerbation of addiction. However, recent research in animal models has proposed alternative models, suggesting that KOR-mediated responses may not act directly on negative valence systems but modulate related processes such as novelty processing. Studies in humans came to similar conclusions that KORs may modulate various aspects of reward processing in a manner that is independent of the hedonic valence traditionally ascribed to them. This broadens the potential understanding of KORs in addiction beyond a unidimensional framework, implicating their role in complex behaviors and treatment approaches that do not align strictly with stress or aversion. These emerging perspectives may inform the development of novel pharmacotherapies targeting KORs for the treatment of substance use disorders, as they highlight the receptor's multifaceted role in addiction.
Another 2015 meta-analysis found no association between lifetime cannabis use and risk of head or neck cancer. Combustion products are not present when using a vaporizer, consuming THC in pill form, or consuming cannabis foods. There is concern that cannabis may contribute to cardiovascular disease, but as of 2018, evidence of this relationship was unclear. Research in these events is complicated because cannabis is often used in conjunction with tobacco, and drugs such as alcohol and cocaine that are known to have cardiovascular risk factors. Smoking cannabis has also been shown to increase the risk of myocardial infarction by 4.8 times for the 60 minutes after consumption. There is preliminary evidence that cannabis interferes with the anticoagulant properties of prescription drugs used for treating blood clots. As of 2019, the mechanisms for the anti-inflammatory and possible pain relieving effects of cannabis were not defined, and there were no governmental regulatory approvals or clinical practices for use of cannabis as a drug.
== O == Severo Ochoa (1905–1993). Spanish and American biochemist at New York University, major contributor to elucidating the genetic code. Nobel Prize in Physiology or Medicine (1959). Member Natl. Acad. Sci. USA. Alexander George Ogston FRS (1911–1996). British biochemist at Oxford University, known for the three-point attachment explanation of how an achiral substance can have a chiral product in the tricarboxylate cycle. Reiji Okazaki (1930–1975). Japanese molecular biologist at Nagoya University, known for discovering Okazaki fragments, an essential step for understanding DNA replication. Tsuneko Okazaki (b. 1933). Japanese molecular biologist at Nagoya University, known for discovering Okazaki fragments, an essential step for understanding DNA replication. L'Oréal-UNESCO Award for Women in Science. Joan Oró (1923–2004). Spanish biochemist at the University of Houston. Prominent for studies of the origin of life. Muriel Wheldale Onslow (1880–1932). British biochemist at Cambridge University, pioneer in biochemical genetics who worked on petal colour in flowers. Alexander Oparin, (1894–1980). Soviet biochemist at Moscow State University, known for his theory on the origin of life in coacervates. Full Member of the USSR Academy of Sciences. Mary Osborn (b. 1940). English cell biologist at the University of Göttingen known for developing techniques for determining protein molecular masses. Mary Jane Osborn (1927–2019). American biochemist at the University of Connecticut, who worked on lipopolysaccharides, and discovered the mechanism of action of methotrexate.
=== Foe === A foe is a unit of energy equal to 1044 joules (≈9.478×1040 BTU) that was invented by physicist Gerry Brown of Stony Brook University. To measure the staggeringly immense amount of energy produced by a supernova, specialists occasionally use the "foe", an acronym derived from the phrase [ten to the power of] fifty-one ergs, or 1051 ergs. This unit of measure is convenient because a supernova typically releases about one foe of observable energy in a very short period of time (which can be measured in seconds).
Sources: en.wikipedia.org
==== Potential path: sludge to food ==== PFOA and PFOS were detected in "very high" (low parts per million) levels in agricultural fields for grazing beef cattle and crops around Decatur, Alabama. The approximately 5000 acres of land were fertilized with "treated municipal sewage sludge, or biosolids". PFOA was also detected in fodder grass grown in these soils and the blood of the cattle feeding on this grass. The water treatment plant received process wastewater from a nearby perfluorochemical manufacturing plant. 3M says they managed their own wastes, but Daikin America "discharged process wastewater to the municipal waste treatment plant". If traced to meat, it would be the first time perfluorochemicals were traced from sludge to food. However, the USDA reported—with a detection limits of 20 parts per billion—non-detectable levels for both PFOA and PFOS in cattle muscle tissue.
In November 2024, after state analysts released a report showing that the state would soon enter a revenue deficit worse than the Great Recession, Moore reiterated a "high bar" for raising taxes and proposed temporarily pausing certain programs that were being implemented under the Blueprint for Maryland's Future. He also proposed shifting state investments toward growing areas of the state's economy—life sciences, information technology, and national defense—and coordinating economic development strategies with local governments. In January 2025, Moore proposed a budget that included $2 billion in spending cuts toward government programs that he described as "not effective nor sustainable", later signing an executive order aimed at reducing inefficiencies in state government. The proposed budget also contained an estimated $819 million in tax reforms, which included new income tax brackets for wealthy individuals and households, and a consolidation of income tax brackets for lower earners; an elimination of the state's inheritance tax and standard deductions; and a cut to the state's corporate tax rate while also requiring combined reporting for companies with subsidiaries. In March 2025, Moore told reporters that he did not support including a sugary drink tax or a "broad business-to-business tax" on services in his budget, but administration officials later told reporters that Moore would consider a package that also included taxes on services direct to consumers as well as businesses.
Rafflesia hasseltii is a parasitic plant species of the genus Rafflesia and the family Rafflesiaceae which is hosted by certain Tetrastigma species. It is native to Sumatra and Peninsular Malaysia. R. hasseltii has by far the widest variation in form, color and pattern of any of the rafflesias.
==== Resolving debate over foreign aid ==== Some voices in the administration continued to point in the opposite direction: for example, Under Secretary of State Herbert Hoover Jr. and the new ICA head, John Hollister, who represented more frugal attitudes. Given the lack of consensus, Eisenhower and Congress conducted in 1956 several studies to give foreign aid policy a more solid basis. Mainly delivered in early 1957, the reports included an updated version of the essay by Millikan and Rostow that C.D. Jackson had circulated in 1954. The overall view that emerged was that sustained development assistance would have long-term benefits for the U.S. position in the world and, more specifically, that developing countries needed substantial financial assistance in the form of low-interest loans. Developing countries particularly needed softer financing to invest in public health systems, schools, and economic infrastructure, for which "hard", commercial lending was unsuitable. Personnel changes soon reflected this change in the administration's view: Christian Herter succeeded Herbert Hoover Jr. as Under Secretary of State in February 1957, Robert Anderson succeeded George Humphrey as treasury secretary in July 1957, and James H. Smith Jr. replaced John Hollister as ICA Director in September 1957. Eisenhower summarized the conclusions in his May 21, 1957 message to Congress: "This past year ... Congressional Committees, the Executive Branch and distinguished private citizens have just examined these programs anew. ... I recommend the following legislative actions: ...
Arbitration by consent, s 240. Workplace determinations, s 275 50% vote to approve by staff after final offer of employer, s 182 Process to approve an agreement, ss 180–186 Agreements approved by FWC, not below NES and pass BOOT, s 55 BOOT, each employee must be better off than in an awards 193 Variation by same process as making: ss 207–224 FWC can approve termination if in public interest, s 225 - back to award unless terms incorporated - or if out of date, it limits productivity, etc.
Sources: en.wikipedia.org
The lyophilised solid is best kept cold, dry and dark, typically at minus twenty degrees Celsius. Moisture and repeated warming cycles are the main causes of degradation. Solutions prepared from the powder are less stable and are normally used quickly.
Reversed-phase liquid chromatography assesses purity, while mass spectrometry confirms molecular mass and detects sequence errors. Amino acid analysis and peptide mapping add structural detail. These techniques are complementary rather than interchangeable.
It is listed as a prohibited peptide hormone by the World Anti-Doping Agency. No medicines regulator has approved it for human use. Import and sale rules vary by country.
It is a synthetic cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone, containing seven amino acids with a lactam ring and a D-configured phenylalanine residue. It is supplied as a lyophilised powder for laboratory research.