alpha-MSH analogue comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-11-01. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic cyclic heptapeptide | Analog of alpha-melanocyte-stimulating hormone |
| Primary receptor family | Melanocortin receptors MC1R through MC5R | Binding is not subtype-selective |
| Development period | 1980s | Synthesized during pigmentation and appetite research |
| Regulatory status | Not an approved medicine | No major regulator has authorized human use |
| Related compound | Afamelanotide | Linear analog studied for photoprotection |
=== Other lawsuits, investigations, and prosecutions === In August 2019, Schmitt withdrew a legal brief that argued that the First Amendment allowed government officials to withhold records from a freedom of information request, following criticism from transparency advocates who noted that the brief did not cite any case law. A Freedom Center of Missouri representative raised concern that the argument is similar to a case involving Governor Mike Parson, which Schmitt had not yet ruled on. Under Schmitt, the attorney general's office sued the city of Marshfield, Missouri, alleging that it maintained a ticket-quota system, in violation of the state law Schmitt had sponsored as state senator banning such quotas. In 2020, the suit ended in a settlement in which the city agreed to maintain a compliance program and have its state officials undergo training on the law. In September 2019, a bipartisan group of state attorneys general, including Schmitt, launched an antitrust investigation against Google. The attorneys general accused Google of prioritizing searches for companies that advertise on the search engine platform in violation of antitrust law.
Paralytic shellfish poisoning (PSP) is one of the four recognized syndromes of shellfish poisoning, which share some common features and are primarily associated with bivalve mollusks (such as mussels, clams, oysters and scallops). These shellfish are filter feeders and accumulate neurotoxins, chiefly saxitoxin, produced by microscopic algae, such as dinoflagellates, diatoms, and cyanobacteria. Dinoflagellates of the genus Alexandrium are the most numerous and widespread saxitoxin producers and are responsible for PSP blooms in subarctic, temperate, and tropical locations. The majority of toxic blooms have been caused by the morphospecies Alexandrium catenella, Alexandrium tamarense, Gonyaulax catenella and Alexandrium fundyense, which together comprise the A. tamarense species complex. In Asia, PSP is mostly associated with the occurrence of the species Pyrodinium bahamense. Some pufferfish, including the chamaeleon puffer, also contain saxitoxin, making their consumption hazardous.
CpG site Also CG site and C-G site. A sequence of DNA in which a cytosine nucleotide is immediately followed by a guanine nucleotide on the same strand in the 5'-to-3' direction; the "p" in CpG refers simply to the intervening phosphate group linking the two consecutive nucleotides.
=== Asia === In Japan, the Japanese Communist Party (JPC) does not advocate for a violent revolution, instead proposing a parliamentary democratic revolution to achieve "democratic change in politics and the economy." There was a resurgent interest in the JPC among workers and the Japanese youth due to the 2008 financial crisis. After the 2008 Malaysian general election, the Socialist Party of Malaysia got Michael Jeyakumar Devaraj as its first Member of Parliament. In the Philippines, the main political party campaigning for democratic socialism is the Akbayan Citizens' Action Party which was founded by Joel Rocamora in January 1998 as a democratic socialist and progressive political party. The Akbayan Citizens' Action Party has consistently won seats in the House of Representatives, with Etta Rosales becoming its first representative. It won its first Senate seat in 2016, when its chairwoman, senator and Nobel Peace Prize nominee Risa Hontiveros was elected. In 2010, there were 270 kibbutzim in Israel. Their factories and farms account for 9% of Israel's industrial output, worth US$8 billion and 40% of its agricultural output, worth over $1.7 billion. Some kibbutzim had also developed substantial high-tech and military industries. Also in 2010, Kibbutz Sasa, containing some 200 members, generated $850 million in annual revenue from its military-plastics industry.
In a mice model of ovalbumin-induced allergic airway disease, 12-HHT and its companion cyclooxygenase metabolites, prostaglandin E2 and prostaglandin D2, but not 12 other lipoxygenase or cycloxygenase metabolites, showed a statistically significantly increase in bronchoalveolar lavage fluid levels after intratracheal ovalbumin challenge; after this challenge, only 12-HHT, among the monitored BLT2 receptor-activating ligands (LTB4, the 12(S) stereoisomer of 12-HETE, and 15(S)-HETE) attained levels capable of activating BLT2 receptors. Also, BLT2 knockout mice exhibited a greatly enhanced response to ovalbumin challenge. Finally, BLT2 receptor expression was significantly reduced in allergy-regulating CD4+ T cells from patients with asthma compared to healthy control subjects. Unlike LTB4 and its BLT1 receptor, which are implicated in contributing to allergen-based airway disease in mice and humans, 12-HHT and its BLT2 receptor appear to suppress this disease in mice and may do so in humans. While further studies to probe the role of the 12-HHT/BLT2 axis in human inflammatory and allergic diseases, the current studies indicate that 12-HHT, acting through BLT2, may serve to promote or limit, inflammatory and to promote allergic responses.
Sources: en.wikipedia.org
=== Pharmacokinetics === Orally administered endoxifen is rapidly absorbed and systemically available. The time to peak (Tmax) is between 4.5 and 6 hours after oral administration. It is not metabolized by cytochrome P450 enzymes. The half-life (t½) life of endoxifen is 52.1 to 58.1 hours.
=== Relationship === Rose's parents forbade their daughter from continuing to date Fred, but she defied their wishes, prompting them to visit Gloucestershire's social services agency to explain that their 15-year-old daughter was having a sexual relationship with an older man, and that they had heard rumours that she had begun to engage in prostitution at Fred's caravan. In response, Rose was placed in a home for troubled teenagers in Cheltenham in August 1969, and only permitted to leave under controlled conditions. When allowed to return home to visit her parents at weekends, Rose almost invariably took the opportunity to visit Fred. On her 16th birthday, Rose left the home for troubled teenagers to return to her parents while Fred was serving a thirty-day sentence for theft and unpaid fines. Upon his release, Rose left her parents' home to move into a flat in Cheltenham with Fred. Shortly thereafter, Fred collected Charmaine and Anne Marie from social services. Rose's father made one final effort to prevent his daughter from seeing Fred, and Rose was examined by a police surgeon in February 1970, who confirmed she was pregnant. In response, Rose was again placed into care but was discharged on 6 March on the understanding she would terminate her pregnancy and return to her family. Instead, Rose opted to live with Fred, resulting in her father forbidding his daughter from ever again setting foot in his household. Three months later Fred and Rose vacated the Cheltenham flat and moved to the ground-floor flat of a two-storey house at 25 Midland Road in Gloucester.
In many species—including all vertebrates—the nervous system is the most complex organ system in the body, with most of the complexity residing in the brain. The human brain alone contains around one hundred billion neurons and one hundred trillion synapses; it consists of thousands of distinguishable substructures, connected to each other in synaptic networks whose intricacies have only begun to be unraveled. At least one out of three of the approximately 20,000 genes belonging to the human genome is expressed mainly in the brain. Due to the high degree of plasticity of the human brain, the structure of its synapses and their resulting functions change throughout life. Making sense of the nervous system's dynamic complexity is a formidable research challenge. Ultimately, neuroscientists would like to understand every aspect of the nervous system, including how it works, how it develops, how it malfunctions, and how it can be altered or repaired. Analysis of the nervous system is therefore performed at multiple levels, ranging from the molecular and cellular levels to the systems and cognitive levels. The specific topics that form the main focus of research change over time, driven by an ever-expanding base of knowledge and the availability of increasingly sophisticated technical methods. Improvements in technology have been the primary drivers of progress. Developments in electron microscopy, computer science, electronics, functional neuroimaging, and genetics and genomics have all been major drivers of progress.
== Release == Portal was first released as part of The Orange Box for Windows and Xbox 360 on October 10, 2007, and for the PlayStation 3 on December 11, 2007. In addition to Portal, The Orange Box includes Half-Life 2 and its two add-on episodes, as well as Team Fortress 2. Portal's inclusion within The Orange Box was considered an experiment by Valve; having no idea of the success of Portal, the bundle provided it a "safety net" via means of these other games. Portal was kept to a modest length in case the game did not go over well with players. The game was released as a standalone retail product on April 9, 2008, with the Windows version also available as a download through Steam. In January 2008, Valve released a special demo titled Portal: The First Slice, free to any Steam user using Nvidia graphics hardware, as part of a collaboration between the two companies. The demo comes packaged with Half-Life 2: Deathmatch, Peggle Extreme, and Half-Life 2: Lost Coast. The demo includes test chambers 00 to 10 (eleven in total). Valve has since made the demo available to all Steam users. Portal is the first Valve-developed game to be added to the OS X-compatible list of games available on the launch of the Steam client for Mac on May 12, 2010, supporting Steam Play, in which buying the game on Macintosh or Windows computer makes it playable on both. As part of the promotion, Portal was offered as a free game for any Steam user during the two weeks following the Mac client's launch. Within the first week of this offer, over 1.5 million copies were downloaded through Steam.
Sources: en.wikipedia.org
No regulator in a major market has approved it for human use. It appears in research settings and in products marketed outside pharmacy channels. Legal status for personal possession varies by country.
Afamelanotide is a linear analog that has received approval in some jurisdictions for a specific photoprotection indication. Melanotan II is cyclic and less selective across melanocortin receptors. The two are related but are not interchangeable in regulatory or clinical terms.
A compound that activates several receptor subtypes may produce effects beyond pigmentation. Selectivity influences which tissues respond and shapes the side-effect profile described in reports. Designing subtype-selective analogs is a stated goal of melanocortin research.
It is a synthetic cyclic heptapeptide and an analogue of alpha-melanocyte-stimulating hormone. The molecule is produced by chemical synthesis rather than extracted from a biological source.