This is a working overview of alpha-MSH, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
Compared with melanotan II, bremelanotide is a smaller cyclic peptide with a more constrained backbone, which affects receptor selectivity and metabolic stability. Published descriptions give a plasma half-life on the order of a few hours after subcutaneous administration, with elimination through hepatic and renal routes and limited plasma protein binding. Central access is inferred from effects observed in animal models, although direct measurement in humans is limited. Handling and storage requirements follow from the peptide backbone, which is susceptible to hydrolysis and oxidation.
The melanocortin system comprises five G protein-coupled receptors, designated MC1 through MC5, that signal mainly through cyclic AMP accumulation. MC1R and MC2R are associated with pigmentation and adrenal steroid production, while MC3R and MC4R are expressed in the central nervous system and influence energy balance and behavior. MC5R appears in exocrine tissues. Natural agonists include alpha-melanocyte-stimulating hormone and adrenocorticotropic hormone, and endogenous antagonists such as agouti-related protein modulate the same sites. This receptor family provides the framework within which bremelanotide activity is described.
Early clinical work used an intranasal formulation, and later programmes switched to subcutaneous delivery for more consistent absorption. A subcutaneous product received regulatory approval in the United States in 2019 for premenopausal women with acquired, generalised hypoactive sexual desire disorder. Approval followed phase 3 trials in which active treatment separated from placebo on desire and distress measures, though the average difference was modest. Labeling carries a caution about transient blood pressure elevation, so cardiovascular history is assessed before prescribing. Questions about durability of benefit beyond several months remain open.
Published discussion sits at the intersection of peptide chemistry, neuroendocrinology and sexual medicine. Trial reports emphasise change scores on validated instruments, while mechanistic papers focus on hypothalamic circuits and receptor selectivity. Because placebo response in this field is large, effect sizes are usually reported with confidence intervals rather than as isolated averages. Reviews note that female and male data sets are not interchangeable and should be read separately. Diagnostic terminology has been revised over time, which complicates comparison between older and newer studies.
| Property | Value | Notes |
|---|---|---|
| Primary receptor target | MC4R | Highest reported agonist potency within the family |
| Secondary receptor activity | MC1R and MC3R | Lower potency than at MC4R |
| Elimination half-life | About 2 to 3 hours | Measured after subcutaneous administration |
| Plasma protein binding | Approximately 44 percent | Species- and assay-dependent |
| Route of administration | Subcutaneous injection | Reviewed product uses a single-use device |
Bremelanotide acts as a non-selective agonist at melanocortin receptors, with reported activity at MC1R, MC3R, MC4R and MC5R. The proposed basis for its central effects is activation of MC4R populations in the hypothalamus, a region associated with appetite and reproductive signalling. Because the peptide carries a net positive charge and polar side chains, it does not cross biological membranes freely, which is one reason oral administration is not the standard route. Effects generally appear within an hour of parenteral administration and are described as centrally mediated rather than peripheral.
Bremelanotide, developed under the code PT-141, is a synthetic cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone. Its structure is Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-OH, with a lactam bridge joining the aspartate and lysine side chains. The molecule has the formula C50H68N14O10 and a monoisotopic mass near 1025 daltons. It is commonly prepared as the acetate salt and appears as a white to off-white lyophilised powder in solid form. The free acid is the pharmacologically relevant species, while the counter-ion improves handling and dissolution.
A definite diagnosis of transfusion-transmitted bacterial infection includes the identification of a positive culture in the recipient (without an alternative diagnosis) as well as the identification of the same organism in the donor blood. Since the advent of HIV testing of donor blood in the mid/later 1980s, ex. 1985's ELISA, the transmission of HIV during transfusion has dropped dramatically. Prior testing of donor blood only included testing for antibodies to HIV. However, because of latent infection (the "window period" in which an individual is infectious, but has not had time to develop antibodies) many cases of HIV seropositive blood were missed. The development of a nucleic acid test for the HIV-1 RNA has dramatically lowered the rate of donor blood seropositivity to about 1 in 3 million units. As transmittance of HIV does not necessarily mean HIV infection, the latter could still occur at an even lower rate. The transmission of hepatitis C via transfusion currently stands at a rate of about 1 in 2 million units. As with HIV, this low rate has been attributed to the ability to screen for both antibodies as well as viral RNA nucleic acid testing in donor blood. Other rare transmissible infections include hepatitis B, syphilis, Chagas disease, cytomegalovirus infections (in immunocompromised recipients), HTLV, and Babesia.
blunt end A term used to describe the end of a double-stranded DNA molecule where the terminal nucleobases on each strand are base-paired with each other, such that neither strand has a single-stranded "overhang" of unpaired bases. This is in contrast to a so-called "sticky end", where an overhang is created by one strand being one or more bases longer than the other. Blunt ends and sticky ends are relevant when ligating multiple DNA molecules, e.g. in restriction cloning, because sticky-ended molecules will not readily anneal to each other unless they have matching overhangs; blunt-ended molecules do not anneal in this way, so special procedures must be used to ensure that fragments with blunt ends are joined in the correct places.
In his introduction to the 1895 edition of Karl Marx's The Class Struggles in France, Engels attempted to resolve the division between gradualist reformist and revolutionary socialists in the Marxist movement by declaring that he was in favour of short-term tactics of electoral politics that included gradualist and evolutionary socialist policies while maintaining his belief that revolutionary seizure of power by the proletariat should remain a key goal of the socialist movement. In spite of this attempt by Engels to merge gradualism and revolution, his effort only diluted the distinction of gradualism and revolution and had the effect of strengthening the position of the revisionists. Engels' statements in the French newspaper Le Figaro in which he argued that "revolution" and the "so-called socialist society" were not fixed concepts, but rather constantly changing social phenomena and said that this made "us [socialists] all evolutionists", increased the public perception that Engels was gravitating towards evolutionary socialism. Engels also wrote that it would be "suicidal" to talk about a revolutionary seizure of power at a time when the historical circumstances favoured a parliamentary road to power which he predicted could happen "as early as 1898." Engels' stance of openly accepting gradualist, evolutionary and parliamentary tactics while claiming that the historical circumstances did not favour revolution caused confusion among political commentators and the public.
== Function == Originating from the embryonic epidermis, the hair follicle evolves into one of the most complex structures in the human body, comprising 7–8 distinct tissue sections. The base of the hair follicle contains the bulb, housing dermal fibroblasts known as the dermal papilla, crucial for morphogenesis and the hair follicle's cyclic activity. Encircling these cells is the matrix cell region, the hair follicle's proliferative compartment, responsible for the formation of different follicle compartments (except the ORS) and the production of crucial structural elements of hair - hair keratins and associated proteins known as KAPs. Keratin is a crucial fibrous protein found in animals, constituting tough structures like hair, feathers, nails, and horns. It's classified based on tissue origin and sulfur content: soft keratins have lower sulfur, while hard keratins, found in hair and claws, contain more sulfur, creating a stronger structure. Keratins belong to two types - acidic Type I and neutral-basic Type II, further categorized into Type I a and b, and Type II a and b. The initial step in forming keratin is the alignment of type I and type II keratin polypeptides to create a heterodimer, which then aggregates into higher-order structural units. Similar to other intermediate filament subunit proteins, a prevalent secondary structure exists: a well-preserved, central alpha-helical domain made up of four coiled-coil segments along with non-helical end-terminal domains that vary in sequences and lengths [14].
Sources: en.wikipedia.org
Belize's rugged geography has also made the country's coastline and jungle attractive to drug smugglers, who use the country as a gateway into Mexico. In 2011, the United States added Belize to the list of nations considered major drug producers or transit countries for narcotics.
In medicine (hematology), bleeding diathesis is an unusual susceptibility to bleed (hemorrhage) mostly due to hypocoagulability (a condition of irregular and slow blood clotting), in turn caused by a coagulopathy (a defect in the system of coagulation). Therefore, this may result in the reduction of platelets being produced and leads to excessive bleeding. Several types of coagulopathy are distinguished, ranging from mild to lethal. Coagulopathy can be caused by thinning of the skin (Cushing's syndrome), such that the skin is weakened and is bruised easily and frequently without any trauma or injury to the body. Also, coagulopathy can be contributed by impaired wound healing or impaired clot formation.
== Shopping bags == Commercial thermal shopping bags, to carry temperature-sensitive purchases home without breaking the cold chain, were first introduced by grocery and other shops in Europe in the mid-1980s. A thermal bag to keep pizzas being delivered hot was invented by Ingrid Kosar in 1983, and is commonly used now. A cool box is very similar in concept, but typically larger and in the form of a rigid box.
==== History ==== All Sendai virus strains belong to the same serotype. The origin of many strains of SeV was described in 1978. Some strains such as Ohita and Hamamatsu were described later. Ohita and Hamanatsu strains were isolated from separate epidemics in laboratory mice. According to the personal memory of Alisa G. Bukrinskaya, who has co-authored numerous publications related to SeV along with Viktor M. Zhdanov, starting in 1961, the Moscow strain of SeV was obtained by Viktor M. Zhdanov of the Ivanovsky Institute of Virology from Japan in the late 1950s or early 1960s, It is reported that the BB1 strain derived from the Moscow virus strain. The strain BB1 was given to the researchers of Institute of Viral Disease Control and Prevention, Beijing, China by researchers of Ivanovsky Institute of Virology, Moscow, Russia in the 1960s.
The School of Clinical Medicine is the medical school of the University of Cambridge in England. The Cambridge Graduate Course in Medicine (A101) is the most competitive course offered by the university and in the UK, and is among the most competitive medical programmes for entry in the world. The school is located alongside Addenbrooke's Hospital and other institutions in multiple buildings across the Cambridge Biomedical Campus.
Sources: en.wikipedia.org
== Awards == Barran was awarded the 2009 Joseph Black award, and the 2020 Theophillus Redwood Award from the Royal Society of Chemistry Analytical Division. Along with a team of researchers 'NosetoDiagnose' she won the Horizon Prize from the Royal Society of Chemistry 2021. She is ranked #3 in the "Human Health Heroes" field on the 2024 Analytical Scientist Power List.
Most drugs were discovered by empirical means, including observation, accident, and trial and error. One famous example is the discovery of penicillin, the first antibiotic in the world. The substance was discovered by Alexander Fleming in 1928 after a combination of unanticipated events occurred in his laboratory during his summer vacation. The Penicillium mold on the petri dish was believed to secrete a substance (later named "penicillin") that inhibited bacterial growth. Large pharmaceutical companies then started to establish their microbiological departments and search for new antibiotics. The screening program for antimicrobial compounds also led to the discovery of drugs with other pharmacological properties, such as immunosuppressants like Cyclosporin A.The discovery of penicillin was a serendipitous (i.e. chance) discovery. Another, more advanced approach to drug discovery is rational drug design. The method is underpinned by an understanding of the biological targets of the drugs, including enzymes, receptors, and other proteins. In the late 19th century, Paul Ehrlich observed the selective affinity of dyes for different tissues and proposed the existence of chemoreceptors in our bodies. Receptors were believed to be the specific binding sites for drugs. The drug-receptor recognition was described as a key-and-lock interplay by Emil Fischer in the early 1890s. It was later found that the receptors can either be stimulated or inhibited by chemotherapeutic agents to attain the desired physiological response.
=== Budget and fiscal position === Danish fiscal policy is generally considered healthy. Government net debt was close to zero at the end of 2017, amounting to DKK 27.3 billion, or 1.3% of GDP. The government sector having a fair amount of financial assets as well as liabilities, government gross debt amounted to 36.1% of GDP at the same date. The gross EMU-debt as percentage of GDP was the sixth-lowest among all 28 EU member countries, only Estonia, Luxembourg, Bulgaria, the Czech Republic and Romania having a lower gross debt. Denmark had a government budget surplus of 1.1% of GDP in 2017. Long-run annual fiscal projections from the Danish government as well as the independent Danish Economic Council, taking into account likely future fiscal developments caused by demographic developments etc. (e.g. a likely ageing of the population caused by a considerable expansion of life expectancy), consider the Danish fiscal policy to be overly sustainable in the long run. In Spring 2018, the so-called Fiscal Sustainability Indicator was calculated by the Danish government and the Danish Economic Council to be 1.2% and 0.9% of GDP, respectively. This implies that under the assumptions employed in the projections, fiscal policy could be permanently loosened (via more generous public expenditures and/or lower taxes) by c. 1% of GDP while still maintaining a stable government debt-to-GDP ratio in the long run.
The structure of somatostatin receptor antagonists is similar to that of the agonists. Some agonists were already approved by the FDA for clinical use, such as In-DTPA-octreotide and Ga-DOTATATE. Development started after the discovery of modifications that can be done to the octreotide group, an ssrt selective subtype agonist, to cause its agonistic effects to be lost and gain antagonistic effects. Different subtype receptor antagonists were later developed. Research has been done mostly on the sstr2 receptor antagonist, as the sstr2 receptor is expressed on most tumors. Somatostatin receptor antagonists are divided by generation based on the type of the subtype receptor antagonist. The first generation consists of sst2-ANT and BASS, which are sstr2 selective; and sst3-ODAN-8, which is selective for sstr3. After initial results of their increased sensitivity to neurocrine tumors appeared, ssrt2 selective antagonists that had even higher affinity were developed. These were LM3, JR10, and JR11, which make up the second generation. JR11 was shown to be the most effective among these 3 antagonists, and compounds that entered further clinical development to act as a PET imaging agent or therapeutic agent carried this subtype antagonist. The presence of a chelator coupled to the subtype antagonist was shown to affect the biological properties., by increasing the binding stability of the radionuclide to the rest of the compound, and increasing the binding affinity to the receptor by allowing conjugation of the radionuclide to the receptor.
Sources: en.wikipedia.org
Reported activity is highest at MC4R, with lower potency at MC1R and MC3R. The MC4R interaction is generally treated as the most relevant to its central effects. Selectivity is not absolute, and activity across the family is dose-dependent.
Indirect evidence from animal studies supports central access, and the proposed mechanism requires it. Direct quantification in humans is limited. How much reaches specific brain regions remains an open question.
Published descriptions give a plasma half-life of roughly two to three hours after subcutaneous administration. Values vary with assay method and study population. The figure is an average rather than a fixed molecular property.
It is a synthetic cyclic peptide that activates melanocortin receptors. It is given by injection and was approved in the United States in 2019 for a specific low-desire diagnosis in premenopausal women. It is not a hormonal therapy.