The short version of prescription control fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-11-22. Anything still debated is marked as such rather than presented as settled.
The compound was developed in the late 1980s and early 1990s by academic researchers investigating melanocortin signaling and pigmentation. Early work explored whether synthetic analogs could reproduce effects of the natural hormone under controlled conditions. The molecule never advanced through the full regulatory pathway required for approval as a medicine. From the mid-2000s onward it appeared in unregulated consumer markets, often distributed through informal channels. That gap between research origins and commercial availability shapes how the compound is discussed today.
Melanotan-2 is a synthetic peptide designed as an analog of alpha-melanocyte-stimulating hormone, a signaling molecule produced in the pituitary and skin. Its structure is a linear chain of seven amino acids that folds into a ring through an internal lactam bridge joining two side chains. The compound is sometimes written as MT-II or MEL-2 in informal and commercial contexts. It belongs to the melanocortin peptide family, a group of short signaling molecules that share a conserved core sequence recognized by melanocortin receptors.
Identity and purity are assessed with chromatographic and mass spectrometric techniques. Reversed-phase high-performance liquid chromatography separates the target peptide from related impurities and degradation products, and the resulting retention time is compared against a reference standard. Mass spectrometry, often coupled to liquid chromatography, confirms molecular mass. Amino acid analysis or peptide mapping can provide additional sequence-level confirmation when required. Results are only as reliable as the reference materials used alongside them.
Regulatory treatment varies by country. In the United States, melanotan-2 is not approved for any indication, and products marketed for human use fall outside the approved drug framework. Some other jurisdictions have placed it under prescription controls or listed it as a prohibited or restricted substance. Online listings frequently describe the material as a research chemical, a category that does not carry the same manufacturing and labelling requirements as approved medicines.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic cyclic heptapeptide | Analog of alpha-MSH with an internal lactam bridge |
| Molecular weight | Approximately 1024 daltons | Free base value; salt forms differ |
| Appearance | White to off-white powder | Usually supplied as a lyophilized solid |
| Solubility | Freely soluble in water | Poorly soluble in nonpolar solvents |
| Typical storage | −20 °C, dry, protected from light | Repeated freeze-thaw cycles degrade peptides |
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.
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.
Regulatory status varies by jurisdiction, and the substance is frequently described as unapproved for therapeutic use. Some authorities classify it alongside prescription-only medicines or controlled categories, while others address it through general consumer protection rules. Analytical surveys have reported mismatches between label claims and measured content in products sold online, although the scope of such testing is limited. Whether these discrepancies are widespread remains an open question. Discussion in the literature therefore tends to combine chemistry, supply-chain observation and policy analysis.
The material is commonly handled as a lyophilized powder in sealed vials. The solid dissolves readily in water and in polar organic solvents, producing a clear solution after reconstitution. Light, heat and repeated freeze-thaw cycles are the concerns most often raised in handling guidance, because peptide bonds and the constrained ring can degrade. Working solutions are generally prepared fresh, and material left in solution is treated as less stable than the dry form. These properties shape how laboratories store and aliquot reference 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.
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.
Melanotan II holds no marketing authorisation from the Food and Drug Administration, the European Medicines Agency, the UK Medicines and Healthcare products Regulatory Agency or Australia's Therapeutic Goods Administration. Products sold under that name are treated as unapproved new drugs, and their sale or import is prohibited in several jurisdictions. Other countries classify the peptide as a prescription-only medicine or place it among controlled substances, so the legal position changes with the destination market. No pharmacopoeial monograph supplies an official specification, because the material is not a licensed pharmaceutical. Consequently, products offered online are not manufactured to a shared public standard.
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.
A manager recounted that there was a lot more separation on the technical side between TikTok and ByteDance by the time he left. Another said TikTok had to employ better data collection practices than Meta or Google due to the scrutiny it received.
The activities of progesterone besides those mediated by the PRs and mPRs are also of significance. Progesterone lowers blood pressure and reduces water and salt retention among other effects via its antimineralocorticoid activity. In addition, progesterone can produce sedative, hypnotic, anxiolytic, euphoric, amnestic, cognitive-impairing, motor-impairing, anticonvulsant, and even anesthetic effects via formation of sufficiently high concentrations of its neurosteroid metabolites and consequent GABAA receptor potentiation in the brain. There are differences between progesterones and progestins, such as medroxyprogesterone acetate and norethisterone, with implications for pharmacodynamics and pharmacokinetics, as well as for efficacy, tolerability, and safety.
=== Railway === Several train stations serve Moscow. The city's ten rail terminals (or vokzals) are the following: Belorussky Kazansky Kiyevsky Kursky Leningradsky Paveletsky Rizhsky Savyolovsky Yaroslavsky Vostochny
==== Possible roles in pathophysiology ==== Astrocytes can transfer mitochondria into adjacent neurons to improve neuronal function. It is therefore plausible that the damage to astrocyte mitochondria seen in GP astrocytes could affect the activity of neurons. A number of hypothalamic functions show declines in aging that may be related to GP astrocytes. For example, GP astrocytes are in close contact with neurons that make a neurotransmitter called dopamine in both the rat and human hypothalamus. The dopamine produced by these neurons is carried to the nearby pituitary gland to inhibit the release of a hormone called prolactin from the pituitary. The activity of dopaminergic neurons declines during aging, leading to elevations in blood levels of prolactin that can provoke breast cancer. An aging-associated change in astrocyte function might contribute to this change in dopaminergic activity. FABP7+ astrocytes are in close contact with neurons in the arcuate nucleus of the hypothalamus that are responsive to a hormone called leptin that is produced by fat cells. Leptin-sensitive neurons regulate appetite and body weight. FABP7+ astrocytes regulate the responsiveness of these neurons to leptin. Mitochondrial damage in these astrocytes could thus alter the function of leptin-sensitive neurons and could contribute to an aging-associated dysregulation of feeding and body weight. GP astrocytes may also be involved in the hypothalamic regulation of overall glucose metabolism.
Sources: en.wikipedia.org
== Return, illness, and death == In 1999, the Panamanian government had sought the extradition of Noriega from the U.S., as he had been tried in absentia and found guilty of murder in Panama in 1995. After Noriega was imprisoned in France, Panama asked the French government to extradite Noriega so he could face trial for human rights violations in Panama. The French government had previously stated that extradition would not happen before the case in France had run its course. On September 23, 2011, a French court ordered a conditional release for Noriega to be extradited to Panama on October 1, 2011. Noriega was extradited to Panama on December 11, 2011, and incarcerated at El Renacer prison to serve the sentences, totalling 60 years, that he had accumulated in absentia for crimes committed during his rule. On February 5, 2012, Noriega was moved to Hospital Santo Tomás in Panama City because of high blood pressure and a brain hemorrhage. He remained in the hospital for four days before being returned to prison. It was announced on March 21, 2012, that Noriega had been diagnosed with a brain tumor, which was later revealed to have been benign. On January 23, 2017, he was released from prison and placed under house arrest to prepare for surgery that would remove the tumor. On March 7, 2017, he suffered a brain hemorrhage during surgery which left him in critical condition in the intensive care unit of Hospital Santo Tomás. Noriega died on May 29, 2017, at the age of 83.
== Life cycle == Like many species of bamboo, black bamboo synchronizes its flowering, with flowering events happening every 40-120 years. According to one source, it has bloomed every 120 years "since records have been kept". It is monocarpic, that is, after flowering, the plants die. Henon bamboo flowers every 120 years and is predicted to flower in the 2020s. Since it is widely distributed in Japan, dieback of its stands may cause serious social and environmental problems. Moreover, Henon bamboo rarely sets fertile seeds, so it is not clear how this species has survived over long periods in Japan.
demethylation The removal of a methyl group (–CH3) from a chemical compound, protein, or other biomolecule, either spontaneously or by enzymatic catalysis. Demethylation is the opposite of methylation; both reactions play important roles in numerous biochemical processes, including in regulating gene expression, as the methylation state of particular residues within particular proteins or nucleic acids can affect their structural conformation in a way that alters their affinity for other molecules, making transcription at nearby genetic loci more or less likely.
Morphine is a highly addictive substance. In a controlled study comparing the physiological and subjective effects of heroin and morphine in individuals formerly addicted to opioids, subjects showed no preference for one drug over the other. Equipotent, injected doses had comparable action courses, with heroin crossing the blood–brain barrier slightly quicker. No difference in subjects' self-rated feelings of euphoria, ambition, nervousness, relaxation, or drowsiness was observed. Short-term addiction studies by the same researchers demonstrated that tolerance developed at a similar rate to both heroin and morphine. When compared to the opioids hydromorphone, fentanyl, oxycodone, and pethidine, former addicts showed a strong preference for heroin and morphine, suggesting that heroin and morphine are particularly susceptible to abuse and addiction. Morphine and heroin also produced higher rates of euphoria and other positive subjective effects when compared to these other opioids. The choice of heroin and morphine over other opioids by former drug addicts may also be because heroin is an ester of morphine and morphine prodrug, essentially meaning they are identical drugs in vivo. Heroin is converted to morphine before binding to the opioid receptors in the brain and spinal cord, where morphine causes subjective effects, which is what the addicted individuals are seeking.
By 1987, companies selling lasers were claiming that they could treat pain, accelerate healing of sports injuries, and treat arthritis, but there was little evidence for this at that time. Mester originally called this approach "laser biostimulation", but it soon became known as "low-level laser therapy". With the adaptation of light emitting diodes it became known as "low-level light therapy"; to resolve confusion around the exact meaning of "low level", the term "photobiomodulation" arose as a synonym.
Sources: en.wikipedia.org
Glucose syrup and corn syrup are widely used in the manufacture of foodstuffs. They are manufactured from starch by enzymatic hydrolysis. For example, corn syrup, which is produced commercially by breaking down maize starch, is one common source of purified dextrose. Such syrups are use in producing beverages, hard candy, ice cream, and jams. Inverted sugar syrup, commonly known as invert syrup or invert sugar, is a mixture of two simple sugars – glucose and fructose – that is made by heating granulated sugar in water. It is used in breads, cakes and beverages for adjusting sweetness, aiding moisture retention and avoiding crystallisation of sugars. Molasses and treacle are obtained by removing sugar from sugarcane or sugar beet juice, as a byproduct of sugar production. They may be blended with the above-mentioned syrups to enhance sweetness and used in a range of baked goods and confectionery including toffees and licorice. In winemaking, fruit sugars are converted into alcohol by a fermentation process. If the must formed by pressing the fruit has a low sugar content, additional sugar may be added to raise the alcohol content of the wine in a process called chaptalisation. In the production of sweet wines, fermentation may be halted before it has run its full course, leaving behind some residual sugar that gives the wine its sweet taste.
== Description == The Wound Man illustrates various injuries that a person might receive through war, accident, or disease: cuts and bruises from multiple weapons, rashes and pustules, thorn scratches, and the bites of venomous animals. The figure also includes some schematic anatomical outlines of several organs within his unusual, transparent abdomen.
Thomas Powers, "The Nuclear Worrier" (review of Daniel Ellsberg, The Doomsday Machine: Confessions of a Nuclear War Planner, New York, Bloomsbury, 2017, ISBN 9781608196708, 420 pp.), The New York Review of Books, vol. LXV, no. 1 (18 January 2018), pp. 13–15. "Presidency in the Nuclear Age", conference and forum at the JFK Library, Boston, October 12, 2009. Four panels: "The Race to Build the Bomb and the Decision to Use It", "Cuban Missile Crisis and the First Nuclear Test Ban Treaty", "The Cold War and the Nuclear Arms Race", and "Nuclear Weapons, Terrorism, and the Presidency". Tom Stevenson, "A Tiny Sun" (review of Fred Kaplan, The Bomb: Presidents, Generals, and the Secret History of Nuclear War, Simon and Schuster, 2021, 384 pp.; and Keir A. Lieber and Daryl G. Press, The Myth of the Nuclear Revolution: Power Politics in the Atomic Age, Cornell, 2020, 180 pp.), London Review of Books, vol. 44, no. 4 (24 February 2022), pp. 29–32. "Nuclear strategists systematically underestimate the chances of nuclear accident... [T]here have been too many close calls for accidental use to be discounted." (p. 32.) Jacobsen, Annie (2024). Nuclear War: A Scenario. Hypothetical minute-by-minute examination of how a nuclear first strike could escalate to global thermonuclear war within 72 minutes, based on interviews with military officials and declassified documents. Lee Billings, "The Quest for a Theory of Everything: A Breakthrough Prize winner warns nuclear war could prevent reaching the holy grail of physics", Scientific American, vol. 335, no. 2 (September 2026), pp. 90–93.
An alternative model, proposed by politicians in Oldenburg and Brunswick, envisaged the foundation of the independent state of "Weser-Ems", that would be formed from the state of Oldenburg, the Hanseatic City of Bremen and the administrative regions of Aurich and Osnabrück. Several representatives of the state of Oldenburg even demanded the inclusion of the Hanoverian districts of Diepholz, Syke, Osterholz-Scharmbeck and Wesermünde in the proposed state of "Weser-Ems". Likewise an enlarged State of Brunswick was proposed in the southeast to include the Regierungsbezirk of Hildesheim and the district of Gifhorn. Had this plan come to fruition, the territory of the present Lower Saxony would have consisted of three states of roughly equal size. The district council of Vechta protested on 12 June 1946 against being incorporated into the metropolitan area of Hanover (Großraum Hannover). If the State of Oldenburg was to be dissolved, Vechta District would much rather be included in the Westphalian region. Particularly in the districts where there was a political Catholicism the notion was widespread, that Oldenburg Münsterland and the Regierungsbezirk of Osnabrück should be part of a newly formed State of Westphalia. Since the foundation of the states of North Rhine-Westphalia and Hanover on 23 August 1946 the northern and eastern border of North Rhine-Westphalia has largely been identical with that of the Prussian Province of Westphalia. Only the Free State of Lippe was not incorporated into North Rhine-Westphalia until January 1947.
The primary medical treatment of acromegaly is to use somatostatin analogues – octreotide (Sandostatin) or lanreotide (Somatuline). Somatostatin analogues are also sometimes used to shrink large tumors before surgery. Because octreotide inhibits gastrointestinal and pancreatic function, long-term use causes digestive problems such as loose stools, nausea, and gas in one-third of people. In addition, approximately 25 percent of people with acromegaly develop gallstones, which are usually asymptomatic. In some cases, octreotide treatment can cause diabetes because somatostatin and its analogues can inhibit the release of insulin. With an aggressive adenoma that is not able to be operated on, there may be a resistance to octreotide in which case a second-generation SSA, pasireotide, may be used for tumor control. However, insulin and glucose levels should be carefully monitored as pasireotide has been associated with hyperglycemia by reducing insulin secretion.
Sources: en.wikipedia.org
It is a synthetic seven-amino-acid peptide modeled on alpha-melanocyte-stimulating hormone. It carries two non-natural substitutions and a cyclic bridge that increase its stability relative to the natural hormone. It circulates as a research chemical and is not an approved medicine.
Melanotan-1, also called afamelanotide, is a shorter linear analog with a different amino acid sequence and no lactam ring. It has been evaluated in formal clinical programs, while melanotan-2 has not. The two are distinct molecules and are not interchangeable.
No. Bremelanotide is a related but distinct cyclic peptide that reached approved status for one specific clinical indication. Melanotan-2 is a separate molecule with its own sequence and properties. Shared ancestry in the melanocortin family does not make them the same substance.
Laboratory confirmation typically combines retention time matching on a chromatographic system with mass measurement. A reference standard of known identity is needed for a meaningful comparison. Sequence-level techniques can add further confirmation.