If you have been reading about MC1R 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 2025-12-04. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Human data remain limited and mostly short-term. Reports describe small trials and observational accounts rather than large controlled studies, so questions about dose-response relationships and long-term effects on melanocytes stay open. Whether repeated exposure alters naevus behaviour is not settled in the published record. Researchers also note that self-administered use outside clinical settings makes actual exposure difficult to quantify. Statements about efficacy and safety should therefore be read as preliminary rather than established.
Freeze-dried melanotan-2 is normally kept as a desiccated powder at minus twenty degrees Celsius or lower, shielded from light and moisture. Peptides of this size degrade through hydrolysis, oxidation and deamidation, and each pathway accelerates as temperature and water activity rise. Repeated freeze-thaw cycles promote aggregation and loss of material, so aliquoting a stock solution before freezing is standard laboratory practice. Once dissolved, the solution is markedly less stable than the powder. In laboratory work, solutions are generally refrigerated and used within days rather than kept for months.
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.
| 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-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.
The compound emerged from research programs in the 1980s that examined analogues of alpha-melanocyte-stimulating hormone for pigmentation and photoprotection. Investigators modified the native sequence to extend activity duration and potency. A related analogue, afamelanotide, was developed within the same broad line of inquiry and eventually gained approval in certain jurisdictions for a rare light-sensitivity condition. Melanotan-2 itself did not progress through the same regulatory route and has no approved therapeutic indication.
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.
The peer-reviewed record is dominated by small early-phase studies, case reports and pharmacovigilance summaries rather than large randomised trials. Papers typically examine tanning response, receptor selectivity or patterns of reported adverse events. Many note that participants obtained the peptide outside a clinical setting, which limits verification of composition and administered amount. Reported events vary widely, and causality is frequently unclear because the identity and purity of self-sourced material are unknown. Open questions include whether repeated melanocortin receptor stimulation produces cumulative effects, and how often label claims match actual content.
Identification in laboratories relies on reversed-phase liquid chromatography coupled with tandem mass spectrometry, with product-ion spectra compared against a certified reference standard. High-resolution mass spectrometry supplies accurate mass confirmation, and peptide mapping after enzymatic digestion separates melanotan II from closely related analogues. Quantitation of seized material is complicated by unknown counter-ions and residual trifluoroacetate left from purification. Immunoassays raised against alpha-melanocyte-stimulating hormone can cross-react, so chromatographic confirmation is normally required. Urinary detection windows are short, and reported limits of detection differ substantially between laboratories.
Rodney local council would lose Orewa, Dairy Flat, and Whangaparaoa but retain the remainder of the current Rodney District. The split areas as well as the current North Shore City would form a Waitemata local council. Waitakere local council would consist of the current Waitakere City as well as the Avondale area. Tamaki Makaurau would consist of the current Auckland City and Otahuhu (excluding CBD) Manukau local council would consist of the urban parts of the current Manukau City and of the Papakura District. Hunua local council would consist of the entire Franklin District, much of which is currently in the Waikato Region, along with rural areas of the current Papakura District and Manukau City. The entire Papakura District would be dissolved between urban and rural councils. The National-led Government responded within about a week. Its plan, which went to a Select Committee, accepted the proposal for supercity and many community boards, but rejected proposals for local councils and, initially, no separate seats for Māori. Public reaction to the Royal Commission report was mixed, especially in regards to the Government's amended proposal. Auckland Mayor John Banks supported the amended merger plans. Criticism of the amended proposal came largely from residents in Manukau, Waitakere and North Shore Cities. In addition, Māori Affairs Minister Pita Sharples spoke against the exclusion of the Māori seats, as recommended by the Royal Commission. Opposition Leader Phil Goff called for a referendum on the issue.
Neuropeptide S (NPS) is a neuropeptide found in human and mammalian brain, mainly produced by neurons in the amygdala and between Barrington's nucleus and the locus coeruleus, although NPS-responsive neurons extend projections into many other brain areas. NPS binds specifically to a G protein-coupled receptor, NPSR. Animal studies show that NPS suppresses anxiety and appetite, induces wakefulness and hyperactivity, and plays a significant role in the extinction of conditioned fear. It has also been shown to significantly enhance dopamine activity in the mesolimbic pathway, and inhibits motility and increases permeability in neurocrine fashion acting through NO in the myenteric plexus in rats and humans.
The primary risks of tobacco usage include many forms of cancer, particularly lung cancer, kidney cancer, cancer of the larynx and head and neck, bladder cancer, esophageal cancer, pancreatic cancer, stomach cancer, and penile cancer. Tobacco smoke can increase the risk of cervical cancer in women. There may be a small increased risk of myeloid leukemia, squamous cell sinonasal cancer, liver cancer, colorectal cancer, cancers of the gallbladder, the adrenal gland, the small intestine, and various childhood cancers. The possible connection between breast cancer and tobacco is still uncertain.
Sources: en.wikipedia.org
Middleton is dyslexic. He read from the New Revised Standard Version of the Bible at the 2011 wedding of his sister Catherine to Prince William. In 2019, he disclosed his struggles with depression and attention deficit hyperactivity disorder, which he attributed to public scrutiny from age 23 as a result of his eldest sister's relationship. He sought treatment in 2017, undertaking cognitive behavioral therapy. Middleton also spent "restorative time" at the Glen Affric Estate, where he has hosted deer-stalking parties. The estate is owned by his sister Philippa's father-in-law. In the same year, he penned a column in the Daily Mail about mental health. Middleton is an ambassador for the Pets As Therapy charity and has credited his dog, Ella, for helping him through his depression. He breeds dogs, owning six, as well as one rescue lamb. Middleton also keeps bees on the grounds of Bucklebury Manor. In April 2020, he founded the Paw Print Fund in aid of animal welfare charities. Middleton was in a relationship with actress Donna Air from 2013 to 2018. Middleton met French financial analyst Alizée Thevenet (b. 30 November 1989) in 2018. She is the daughter of retired diplomat Jean-Gabriel Thevenet. Middleton and Alizée announced their engagement in September 2019. On 11th September 2021, Alizée's mother, along with James's family, attended the wedding in the village of Bormes-les-Mimosas in the south of France where Alizée's family lives. Alizée's father had died some months before the wedding.
In diabetes mellitus (by far the most common cause of chronic hyperglycemia), treatment aims at maintaining blood glucose at a level as close to normal as possible, in order to avoid serious long-term complications. This is done by a combination of proper diet, regular exercise, and insulin or other medication such as metformin. Those with hyperglycaemia can be treated using sulphonylureas or metformin or both. These drugs help by improving glycaemic control. Dipeptidyl peptidase-4 inhibitor alone or in combination with basal insulin can be used as a treatment for hyperglycemia with patients still in hospital. Hyperglycemia can also be improved through minor lifestyle changes. Increasing aerobic exercise to at least 30 minutes a day causes the body to make better use of accumulated glucose since the glucose is being converted to energy by the muscles. Calorie monitoring, with restriction as necessary, can reduce over-eating, which contributes to hyperglycemia. Diets higher in healthy unsaturated fats and whole-wheat carbohydrates such as the Mediterranean diet can help reduce carbohydrate intake to better control hyperglycemia. Diets such as intermittent fasting and ketogenic diet help reduce calorie consumption which could significantly reduce hyperglycemia. Carbohydrates are the main cause for hyperglycemia. Non-whole-wheat items should be substituted by whole-wheat items. Although fruits can be nutritious, fruit intake should be limited due to high sugar content.
Periodic actin rings – A periodic structure constructed of evenly spaced actin rings is found in axons. In this structure, the actin rings, together with spectrin tetramers that link the neighboring actin rings, form a cohesive cytoskeleton that supports the axon membrane. The structure periodicity may also regulate the sodium ion channels in axons.
Sources: en.wikipedia.org
This direct and indirect economic contraction caused the city to lose property taxes, wage taxes, and population (and thus consumer demand). The closed auto plants were also often abandoned in a period before strong environmental regulation, causing the sites to become so-called "brownfields", unattractive to potential replacement businesses because of the pollution hangover from decades of industrial production. The pattern of the deteriorating city by the mid-1960s was visibly associated with the largely departed auto industry. The neighborhoods with the most closed stores, vacant houses, and abandoned lots were in what had formerly been the most heavily populated parts of the city, adjacent to the now-closed older major auto plants. By the 1970s and 1980s, the auto industry suffered setbacks that further impacted Detroit. The industry encountered the rise of OPEC and the resulting sharp increase in gasoline prices. It faced new and intense international competition, particularly from Italian, Japanese and German automobile manufacturers. Chrysler avoided bankruptcy in the late 1970s only with the aid of a federal bailout. GM and Ford also struggled financially. It also relocated ever more of its manufacturing to lower-cost states in the U.S. and to low-income countries. Detroit's residents thus had access to fewer and fewer well-paying, secure auto manufacturing jobs. The leadership of Detroit failed to diversify the city's industry beyond automotive manufacturers and related industries.
This mosaicity allows for substantial shedding of tumor cells into the vasculature, possibly contributing to the appearance of circulating tumor cells in the peripheral blood of patients with malignancies. The subsequent growth of such metastases will also require a supply of nutrients and oxygen and a waste disposal pathway. Endothelial cells have long been considered genetically more stable than cancer cells. This genomic stability confers an advantage to targeting endothelial cells using anti-angiogenic therapy, compared to chemotherapy directed at cancer cells, which rapidly mutate and acquire drug resistance to treatment. Thus, endothelial cells are thought to be an ideal target for therapies against cancer.. Currently, there have been multiple clinical trials using anti-angiogenic therapies in combination with other therapeutic agents (e.g chemotherapy for treatment of various cancers.
=== Founding and early years === On June 20, 1919, Roy W. Allen opened his first root beer stand in Lodi, California. The first day was for a homecoming celebration of soldiers who returned from battle in World War I. The following day, his stand was open for regular customers, selling root beer glasses for 5 cents (equivalent to $0.93 in 2025). The following year, Allen opened a second stand in Stockton, California. Shortly afterward, the effect of the period of prohibition that existed in the United States from 1920 to 1933 gave Allen and his stand with a beverage with "beer" in the name a heavy rebound. Four years later, A&W began when Allen and Frank Wright opened their drive-in restaurant in Sacramento, California, combining both of their initials for the name, and selling the root beer from Allen's stand. Curbside service was provided by tray boys and tray girls. In 1924, Allen purchased Frank Wright's stake in the business. In 1925, Allen began franchising the root beer, while the franchisee added the other menu items and operated at their discretion. Most of the restaurants that opened under this scheme were on the highways of the Central Valley region, mainly for travelers. This may have arguably been the first successful food-franchising operation. Allen sold the company in 1950 and retired. A lot of World War I veterans eventually founded A&W franchises throughout the US, while some of their descendants still own franchises. A&W's initial menu relied heavily on root beer and snacks, such as popcorn and peanuts, as well as sandwiches on sliced bread. In 1927, J.
Pterophyllum scalare, most commonly referred to as angelfish or freshwater angelfish, is the most common species of Pterophyllum kept in captivity. It is native to the Amazon Basin in Peru, Colombia, and Brazil. Particularly to the Ucayali river in Peru, the Oyapock River in French Guiana, the Essequibo River in Guyana, the Solimões, the Amapá, and the Amazon rivers in Brazil. It is found in swamps or flooded grounds where vegetation is dense and the water is either clear or silty. Its native waters range from a neutral pH of 7.0 down to near 6.0, with a general water hardness (gH) range of 3 to 10 °dH, and water temperature ranging from 26 to 30 °C (75 to 86 °F). This is the species of angelfish most frequently found in the aquarium trade. A similar (cross-breeding possible) P. scalare exists in the Rio Orinoco. They are of the same size and shape, the only difference being the stripes; the Orinoco P. scalare has thinner, but dual, stripes. The diet of Pterophyllum scalare consists of a wide spectrum of prey; they feed on tiny fish fry and younger, juvenile fishes, young and mature shrimps, crabs, prawns, various worms, mosquito larvae, and water bugs. Additionally, they will opportunistically catch any smaller-sized floating insects that have fallen onto the surface of the water.
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.
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.