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.
Last reviewed on 2026-02-20. Where a claim depends on a specific study, the study is described rather than over-claimed.
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 |
These large protein complexes may act as spacers between the sheets of stromal thylakoids. The number of thylakoids and the total thylakoid area of a chloroplast is influenced by light exposure. Shaded chloroplasts contain larger and more grana with more thylakoid membrane area than chloroplasts exposed to bright light, which have smaller and fewer grana and less thylakoid area. Thylakoid extent can change within minutes of light exposure or removal.
== Composition == Sweet whey and acid whey are similar in gross nutritional analysis. By mass both contain 93% water, about 0.8% protein, and about 5.1% carbohydrates. Sweet whey contains about 0.4% fat while sour whey contains about 0.1% fat. The carbohydrates are mainly lactose. The proteins are known as lactalbumin. Whey also contains some minerals.
The study of the effect of infectious agents on metabolism is still in its early stages. Gut flora has been shown to differ between lean and obese people. There is an indication that gut flora can affect the metabolic potential. This apparent alteration is believed to confer a greater capacity to harvest energy contributing to obesity. Whether these differences are the direct cause or the result of obesity has yet to be determined unequivocally. The use of antibiotics among children has also been associated with obesity later in life. An association between viruses and obesity has been found in humans and several different animal species. The amount that these associations may have contributed to the rising rate of obesity is yet to be determined.
In Early June, German Forces (estimated at 9 divisions with tanks and artillery) began concentrating in the Lepel-Chashniki area. By June 10, the Germans had fortified the Lepel-Borisov Highway with Trenches and pillboxes every 100 meters, trapping the partisans. The Brigade was forced to retreat into the marshy terrains of Lake Palik. Under constant artillery fire and aerial bombardment, the partisans were pushed back into the forests, where they faced severe supply issues. Records indicate that during the height of the encirclement, the encircled partisans were suffering from extreme famine and were surviving on grass and animal hides.
Biological machines are considered to be nanoscale devices (such as molecular proteins) in a living system that convert various forms of energy to mechanical work in order to drive crucial biological processes such as intracellular transport, muscle contractions, ATP generation and cell division.
Sources: en.wikipedia.org
A member of Parliament is a member of either of the two houses of the Indian Parliament: Lok Sabha (lower house) and Rajya Sabha (upper house). Lok Sabha has 543 seats, all of whom are directly elected by the citizens of India from each parliamentary constituency of states and union territories via first-past-the-post voting. Rajya Sabha can have 245 members, of which 238 members are indirectly elected. Of these 238 members, 229 belong to the state legislatures and 9 belongs to the union territories of Delhi, Puducherry, and Jammu and Kashmir, and are elected by using the single transferable vote method of proportional representation. The remaining 12 members are nominated by the president for their contributions to art, literature, science, and social services. Each state has a fixed number of representatives allocated in each chamber, in order of their respective populations. The state of Uttar Pradesh has the greatest number of representatives in both houses. The person which secures the support of more than half the seats in the Lok Sabha forms the Government. To form the government, parties may form a coalition. The term of a member of the Rajya Sabha is six years, while Lok Sabha members are elected for a term of five years, unless the house is dissolved sooner. Rajya Sabha is a permanent house that is not subject to dissolution, and one third of the members retire every two years.
John Lilley states, "...neutron-induced fission generates extra neutrons which can induce further fissions in the next generation and so on in a chain reaction. The chain reaction is characterized by the neutron multiplication factor k, which is defined as the ratio of the number of neutrons in one generation to the number in the preceding generation. If, in a reactor, k is less than unity, the reactor is subcritical, the number of neutrons decreases and the chain reaction dies out. If k > 1, the reactor is supercritical and the chain reaction diverges. This is the situation in a fission bomb where growth is at an explosive rate. If k is exactly unity, the reactions proceed at a steady rate and the reactor is said to be critical. It is possible to achieve criticality in a reactor using natural uranium as fuel, provided that the neutrons have been efficiently moderated to thermal energies." Moderators include light water, heavy water, and graphite. According to John C. Lee, "For all nuclear reactors in operation and those under development, the nuclear fuel cycle is based on one of three fissile materials, 235U, 233U, and 239Pu, and the associated isotopic chains. For the current generation of LWRs, the enriched U contains 2.5~4.5 wt% of 235U, which is fabricated into UO2 fuel rods and loaded into fuel assemblies." Lee states, "One important comparison for the three major fissile nuclides, 235U, 233U, and 239Pu, is their breeding potential.
==== Catechol O-methyltransferase (COMT) inhibitors ==== Entacapone (Comtan) – catechol O-methyltransferase (COMT) inhibitor Opicapone (BIA 9-1067; BIA-91067; Ongentys; ONO-2370) – catechol O-methyltransferase (COMT) inhibitor [341] Tolcapone (RO-407592; Tasmar) – catechol O-methyltransferase (COMT) inhibitor [342]
The functional group of nitriles containing the C≡N triple bond is referred to as the nitrile or cyano group. If the nitrile is the highest-ranking functional group, the suffix -nitrile is added to the name of the parent compound. The triply bonded carbon atom is, as always, included in the parent chain. Alternatively, the ending -carbonitrile may be used (analogous to -carboxylic acid), in which case the carbon atom is not counted as part of the parent chain. This ending must be used if the nitrile group is attached to a ring (as in cyclopentanecarbonitrile) or if not all carbon atoms are part of the parent chain, which is necessarily the case when more than two nitrile groups are present, as these can only be located at the termini of the chain. Due to their relationship to carboxylic acids (the nitrile carbon has the same oxidation state as the carboxyl carbon), trivial names are often derived from the corresponding carboxylic acids using the ending -onitrile (for example, benzoic acid to benzonitrile). If the nitrile function is not the principal functional group in the molecule, the prefix cyano- is used together with the appropriate locant. In this case as well, the triple-bonded carbon atom is not counted as part of the parent chain.
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.