If you have been reading about melanocortin receptor and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-07-18. Numbers and descriptions here follow the published literature rather than marketing material.
Melanotan II is a synthetic cyclic heptapeptide that acts as an agonist at melanocortin receptors. It was designed as a structural analogue of alpha-melanocyte-stimulating hormone, the endogenous peptide involved in pigment production. The analogue carries a lactam bridge that constrains the ring and slows enzymatic breakdown relative to the native hormone. In research literature it appears under several abbreviations, and naming conventions are not fully standardized. Published descriptions usually place it within the broader melanocortin agonist family.
Receptor binding at MC1R on melanocytes raises intracellular cyclic AMP and increases expression of tyrosinase and related enzymes. The downstream result is greater synthesis of eumelanin, the dark pigment, without ultraviolet exposure acting as the trigger. The compound is not selective, however, and also engages MC3R, MC4R and MC5R, which are expressed in the central nervous system and elsewhere. That lack of selectivity is the explanation usually offered for effects reported outside pigmentation, including appetite suppression and nausea. Selectivity remains a central theme in comparative studies of related peptides.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic cyclic heptapeptide | Melanocortin receptor agonist |
| Molecular formula | C50H69N15O9 | Neutral form, mass near 1024.2 g/mol |
| Primary targets | MC1R, MC3R, MC4R, MC5R | Binding is non-selective across subtypes |
| Related compounds | Alpha-MSH, melanotan I, afamelanotide | Structurally or functionally related peptides |
| Common abbreviations | MT-II, MT-2 | Naming in the literature is not uniform |
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.
Activity is attributed to agonism at melanocortin receptors, particularly MC1R and MC4R. Activation of MC1R on melanocytes increases melanin synthesis, which underlies the reported tanning effect. MC4R engagement in the central nervous system is linked to appetite suppression and to effects on sexual arousal reported in early clinical studies. Those studies were small and were not designed to establish efficacy or long-term safety. Receptor selectivity among the melanocortin subtypes is not absolute, which complicates attribution of any effect to a single pathway.
Receptor studies place melanotan-2 among non-selective melanocortin agonists, binding MC1R, MC3R, MC4R and MC5R rather than a single subtype. Activation of MC1R on cutaneous melanocytes raises tyrosinase activity and shifts pigment synthesis toward eumelanin, which is darker and more photostable than pheomelanin. Central receptors, particularly MC4R, are associated with appetite suppression and with reported effects on sexual function. Because subtype selectivity is low, the same molecule engages pigment, metabolic and vascular pathways at once, and this breadth is a common explanation offered for the range of adverse events described in user reports.
No regulatory authority has approved melanotan-2 for human use, and several countries classify it as a prescription-only or controlled substance, which restricts lawful supply. Material sold online is generally labelled as a research chemical and is not required to meet pharmaceutical standards of identity or purity. Published human data consist mainly of small uncontrolled studies, case reports and adverse-event notifications, so the evidence base is descriptive rather than confirmatory. Whether repeated melanocyte stimulation alters long-term naevus behaviour remains an open question that no completed trial has resolved.
Lundberg, M.D, recommended that third-party payers and the public should question paying for this procedure "until or unless additional honest experimentation demonstrates an actual effect." There is no good medical evidence for the effectiveness of therapeutic touch. A Cochrane systematic review, first published in 2004, found "[t]here is no robust evidence that TT promotes healing of acute wounds", but in 2016, the authors retracted it after the validity of the reviewed studies was questioned. The American Cancer Society notes, "Available scientific evidence does not support any claims that TT can cure cancer or other diseases."
Amine Precursor Uptake – for high uptake of amine precursors including 5-hydroxytryptophan (5-HTP) and dihydroxyphenylalanine (DOPA). Decarboxylase – for high content of the enzyme amino acid decarboxylase (for conversion of precursors to amines).
== Signs and symptoms == Trauma from a gunshot wound varies widely based on the bullet, velocity, mass, entry point, trajectory, affected anatomy, and exit point. Gunshot wounds can be particularly devastating compared to other penetrating injuries because the trajectory and fragmentation of bullets can be unpredictable after entry. Moreover, gunshot wounds typically involve a large degree of nearby tissue disruption and destruction caused by the physical effects of the projectile correlated with the bullet velocity classification. The immediate damaging effect of a gunshot wound is typically severe bleeding with the potential for a type of shock known as hypovolemic shock, a condition characterized by inadequate delivery of oxygen to vital organs. In the case of traumatic hypovolemic shock, this failure of adequate oxygen delivery is due to blood loss, as blood is the means of delivering oxygen to the body's constituent parts. Besides blood loss, internal bleeding can lead to complications. Devastating effects can result when a bullet strikes a vital organ such as the heart, lungs, or liver, or damages a component of the central nervous system such as the spinal cord or brain. It can lead to organ failure and death. Common causes of death following gunshot injury include bleeding, low oxygen caused by pneumothorax, catastrophic injury to the heart and major blood vessels, and damage to the brain or central nervous system.
Sources: en.wikipedia.org
A similar promotion was held in September 2011, near the start of a traditional school year, encouraging the use of the game as an educational tool for science and mathematics. Valve wrote that they felt that Portal "makes physics, math, logic, spatial reasoning, probability, and problem-solving interesting, cool, and fun", a necessary feature to draw children into learning. This was tied to Digital Promise, a United States Department of Education initiative to help develop digital tools for education, which Valve is part of. Portal: Still Alive was announced for Xbox Live Arcade at the 2008 E3 convention, and was released on October 22, 2008. It features the original game, 14 new challenges, and new achievements. The additional content was based on levels from the map pack Portal: The Flash Version created by We Create Stuff and contains no additional story-related levels. According to Valve spokesman Doug Lombardi, Microsoft had previously rejected Portal on the platform due to its large size. Portal: Still Alive was well received by reviewers. 1UP.com's Andrew Hayward stated that, with the easier access and lower cost than paying for The Orange Box, Portal is now "stronger than ever". IGN editor Cam Shea ranked it fifth on his top 10 list of Xbox Live Arcade games. He stated that it was debatable whether an owner of The Orange Box should purchase this, as its added levels do not add to the plot. However, he praised the quality of the new maps included. The game ranked 7th in a later list of top Xbox Live Arcade titles compiled by IGN's staff in September 2010.
=== Fat distribution === In hormone therapy, trans women often experience slight weight gain as men generally carry higher levels of visceral fat compared to subcutaneous fat, and less fat overall compared to women. Over months and years, HRT causes the body to accumulate new fat in a feminine pattern (gynoid fat). Unlike abdominal fat, gynoid fat has little effect on overall health except in the case of severe excess or postural changes. Gynoid fat will accumulate in the hips, lower belly, thighs, buttocks, pubis, upper arms, and breasts while the body burns fat in the ribcage, upper waist, shoulders, and back. However, fat will not simply move from one spot to another. There must be sufficient caloric intake to deposit gynoid fat, and sufficient activity to burn android fat.
=== 1947–1969: Unions and foundations === The Nederlandse Radio Unie (Netherlands Radio Union; NRU) was established in 1947. After several failed attempts to create a public broadcasting system and link up with a national station, the NRU was created as a union of broadcasting associations that provided operational support. The associations were responsible for their output, but studios, orchestras, and outside broadcast facilities were managed by the NRU. Weekly radio plays were also the domain of the NRU and would run until 1986. The NRU became the Dutch founding member of the European Broadcasting Union in 1950. Meanwhile, the Nederlandse Televisie Stichting (Netherlands Television Foundation; NTS) was created in 1951, two years after public television returned to the airwaves. The NTS served as a similar organisation to the NRU, in that broadcast and transmission facilities were supplied to member associations for making programmes. It was not until 1956 that the NTS itself produced its first programme, a news bulletin called the NTS Journaal. This was followed by a sports round-up, Sport in Beeld (Sports Illustrated) in 1959, and 1967 Langs de Lijn (Along the Line), a joint production of several broadcasting associations. On 15 October 1967, Willem Leonard Oltmans interviewed the de Mohrenschildts for the NTS, which resulted in a 40-minute film that was the only full-length filmed interview of George de Mohrenschildt. However, the film, which was kept at Hilversum, disappeared in 1975.
Sources: en.wikipedia.org
The district's arterial roads are laid out on a grid system of north–south and east–west, corresponding to the concession roads of the original township, laid out to facilitate the establishment of farming communities. Kingston Road and Danforth Avenue were laid out prior to surveying the township, and both run diagonally in a southwest–northeast direction across the south end of Scarborough. From north to south, the major east–west arterial roads are Steeles Avenue, Finch Avenue, Sheppard Avenue, Ellesmere Road, Lawrence Avenue, Eglinton Avenue and St. Clair Avenue. From west to east, the major north–south arterial roads are Victoria Park Avenue, Pharmacy Avenue, Warden Avenue, Birchmount Road, Kennedy Road, Midland Avenue, Brimley Road, McCowan Road, Bellamy Road North, Markham Road, Scarborough Golf Club Road, Neilson Road, Morningside Avenue, Meadowvale Road and Port Union Road. Kingston Road was formerly Ontario Highway 2, and was the main highway through the district until the building of Highway 401, which runs east–west across the district, with six to eight lanes in each direction. The short, minor freeway Highway 2A runs parallel to Lake Ontario in the eastern part of Scarborough.
July 1971: The association "Choisir la cause des femmes" is created — with philosopher Simone de Beauvoir and lawyer Gisèle Halimi — to demand the repeal of the 1920 law criminalizing abortion. January 3, 1972: Law on parentage. It opens the right for the mother to challenge, under certain conditions, the presumption of the husband's paternity. January 3, 1972: Law on the stay-at-home mother's allowance. April 24, 1972: Decree applying Article 4 of Law 67-1176 of December 28, 1967, on birth control and repealing Articles L. 648 and L. 649 of the Public Health Code. July 13, 1972: Law establishing the general status of military personnel; access to military careers is not subject to sex-based discrimination. August 16, 1972: Decree on the specific status of the corps of national police inspectors, in which women are allowed to apply. December 22, 1972: Law affirming the principle of equal pay between genders. January 2, 1973: Law on the Labor Code, which updates it and includes provisions on women's work. January 9, 1973: Law amending and supplementing the French Nationality Code and concerning certain provisions related to French nationality; it notably authorizes the transmission of nationality by the mother to her child, whether the child is "legitimate or illegitimate." March 23, 1973: Decree establishing the special status of female military corps.
Lula met with Pope Francis on the Vatican City on 12 June after his diner with Italian President Sergio Mattarella, during the meeting at Paul VI's room, they reportedly discussed "peace and reconciliation, environmental preservation, respect for indigenous populations and the fight against hunger, inequality and poverty in the world", according to Brazilian and Holy See officials, although there was no explicit mention to the current Russo-Ukrainian war, Lula reportedly wanted to talk about a possible peaceful solution of the conflict with the Pope, but neither side mentioned any talks about that particular subject. Lula gave the Pope an engraving of the Holy Family made by Pernambuco artist J. F. Borges, while Rosângela brought the Pontiff an image of Our Lady of Nazaré, patroness of the Amazon, while the Pope gave Lula and Janja a bronze art with the phrase "Peace is a fragile flower", he also presented the couple with a copy of his Message of Peace for 2023, the document on Human Fraternity and the book with the prayer he did in a deserted St. Peter's Square, on 27 March 2020, praying for the end of the COVID-19 pandemic, Lula and Janja also invited the priest to travel to Pará to participate in the "Círio" in October of that year, but acceptance must depend on the state of health of the Pontiff, who was discharged from his most recent hospitalization, the second in two months, on Friday, after the meeting with the Pope, Lula had met with Dom Edgar Peña Parra, responsible for General Affairs at the Vatican Secretariat of State.
Acetoxolutamide is a nonsteroidal androgen and selective androgen receptor modulator (SARM) which was described in 2000 and was never developed or marketed for medical use. It was derived from structural modification of the nonsteroidal antiandrogen bicalutamide and the nonsteroidal SARM acetothiolutamide. Acetoxolutamide shows greatly improved pharmacokinetic properties and anabolic and androgenic potency relative to acetothiolutamide in animals. It is the (2R) enantiomer of andarine (also known as acetamidoxolutamide or androxolutamide).
Sources: en.wikipedia.org
It is a synthetic cyclic heptapeptide and a non-selective melanocortin receptor agonist. Structurally it is modelled on alpha-melanocyte-stimulating hormone, a peptide that occurs naturally in the body.
Activation of MC1R increases pigment synthesis independently of ultraviolet exposure, which is the mechanism usually cited for darkening without sun exposure. Ultraviolet light still influences skin response through separate biological pathways.
Because the peptide binds several melanocortin receptor subtypes, its effects are not confined to pigmentation. This complicates interpretation of both intended and unintended outcomes reported in studies.
It is a synthetic cyclic peptide designed as an analog of alpha-melanocyte-stimulating hormone. It acts on melanocortin receptors and is best known from research into pigmentation. It is not an approved pharmaceutical product.