Everything below concerns 胃饥饿素受体. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-03-18. Where a claim depends on a specific study, the study is described rather than over-claimed.
Ipamorelin 是一种合成五肽，在 20 世纪 90 年代被报道为生长激素促分泌剂。其结构基于胃饥饿素受体激动剂的设计思路，但并非天然激素。早期药理学研究显示，它可刺激垂体释放生长激素，而对应激激素轴的影响相对较小。该化合物常被用作研究生长激素调节通路的工具分子。
在机制层面，ipamorelin 与生长激素促分泌受体 1a 型结合，该受体也介导胃饥饿素的多种效应。受体激活后，细胞内信号促进生长激素从垂体前叶释放。由于对促肾上腺皮质激素和皮质醇的刺激较弱，它被视为选择性较高的促分泌剂。这种选择性在动物模型和少量人体研究中被观察到，但人体数据仍然有限。
Activity is mediated mainly through the growth hormone secretagogue receptor, now generally called the ghrelin receptor or GHS-R1a. Binding at this G-protein-coupled receptor triggers phospholipase C signaling, calcium mobilization, and release of growth hormone from pituitary somatotrophs. Reports describe less pronounced stimulation of adrenocorticotropic hormone and prolactin compared with earlier secretagogues such as hexarelin or GHRP-6. Selectivity figures vary between assay systems, so the degree of separation from other secretagogues is an area of ongoing comparison rather than a fixed constant.
In animal and early human studies, ipamorelin produces pulsatile growth hormone release and a secondary rise in insulin-like growth factor 1. The magnitude and duration of that rise depend on route, sampling schedule, and the baseline endocrine state of the subject. Whether repeated exposure alters the response over time is not firmly settled, since some reports describe stable pulsatility while others note attenuation. Most published data come from small samples, which limits the strength of any general claim about long-term behavior.
Ipamorelin is a synthetic pentapeptide that belongs to the growth hormone secretagogue class of compounds. Its sequence is Aib-His-D-2-Nal-D-Phe-Lys-NH2, a structure that differs from natural ghrelin in length and in the presence of non-natural amino acid residues. Early laboratory work described it as a comparatively selective agent that stimulates growth hormone release with limited effect on other pituitary hormones. The compound is supplied as a lyophilized solid for research use and has no identified natural source in the body.
| Property | Value | Notes |
|---|---|---|
| 分子式 | C38H49N9O5 | 五肽，含非天然氨基酸残基 |
| 分子量 | 711.85 g/mol | 理论值，盐形式可能略有差异 |
| 外观 | 白色至类白色粉末 | 冻干粉常见 |
| 溶解性 | 易溶于水 | 也可溶于部分极性有机溶剂 |
| 储存条件 | -20°C，干燥避光 | 长期保存通常推荐 |
Common solvents for laboratory work include water, buffered saline, and dimethyl sulfoxide. Once dissolved, the peptide is exposed to hydrolysis and oxidation, and alkaline conditions accelerate breakdown. Low-binding plasticware and the addition of a carrier protein reduce losses to container surfaces, which can otherwise be substantial at low concentrations. Solutions are typically kept cold and used within days. Investigators working with the compound generally prepare fresh working dilutions rather than storing dilute stocks, and they avoid repeated warming of the same vial.
Reversed-phase high-performance liquid chromatography is the standard method for purity assessment, most often on a C18 column with a water and acetonitrile gradient and trifluoroacetic acid or formic acid as an ion-pairing agent. Mass spectrometry by electrospray or matrix-assisted laser desorption confirms the expected mass and reveals truncated or modified sequences. Amino acid analysis and sequencing provide orthogonal structural evidence. Typical impurities include deletion sequences, oxidized products, and dimeric species. Detection wavelength, usually 214 or 220 nanometers, should be reported because response factors differ between peptides.
Purity is normally reported as a percentage of total peak area, a figure that does not account for water content, residual solvents, or counterions. Trifluoroacetate and acetate are the most frequent counterions in lyophilized peptides, and they shift the true peptide content away from the mass of the powder. A separate quantitative assay is therefore needed to state content accurately. Certificates of analysis often omit these details, which makes batch-to-batch comparison difficult and limits conclusions drawn when results from different suppliers are compared.
从用途定位看，ipamorelin 目前主要以研究用肽的身份被讨论，未见主要药品监管机构将其批准为治疗药物。市售材料通常标注仅供研究使用，不得用于人体或诊断程序。文献中它常与生长激素促分泌素、GHS-R1a 激动剂、胃饥饿素拟似物等表述并列出现。既有研究的样本量普遍偏小，因此对其效应强度与一致性的描述应保持谨慎。
Ipamorelin 是一种合成五肽，序列为 Aib-His-D-2-Nal-D-Phe-Lys-NH2，分子式 C38H49N9O5，游离碱分子量约 711.85 g/mol。它属于生长激素促分泌素（GHS）家族，作用靶点是胃饥饿素受体 GHS-R1a。该化合物由诺和诺德的研究团队在二十世纪九十年代末报道，设计目标是提高对生长激素释放的选择性。C 端酰胺化与 N 端 Aib 残基是两个用于抵抗肽酶降解的结构特征。
At the molecular level, ipamorelin acts as an agonist at the growth hormone secretagogue receptor, also called the ghrelin receptor or GHS-R1a. Binding to this receptor on pituitary somatotroph cells triggers a signaling cascade that leads to growth hormone release. The effect is mediated through phospholipase C and calcium mobilization rather than through the cyclic AMP pathway used by growth hormone releasing hormone. The two pathways are complementary, and combined stimulation produces a larger response than either alone.
Compared with other secretagogues such as GHRP-2, GHRP-6, and hexarelin, ipamorelin is described as more selective. Published animal work reports little or no increase in adrenocorticotropic hormone, cortisol, or prolactin at doses that release growth hormone. This selectivity is the property most often cited in the research literature. Whether the same profile holds across species and dosing schedules remains an open question, since human data are limited and come largely from small studies.
Ipamorelin is a synthetic pentapeptide that belongs to the growth hormone secretagogue family. Its sequence is Aib-His-D-2-Nal-D-Phe-Lys-NH2, and its molecular mass is approximately 711.9 daltons. The compound was described in the late 1990s by researchers seeking molecules that release growth hormone with fewer side effects than earlier secretagogues. It is a laboratory and research compound, not an approved medicine in most jurisdictions.
Analytical confirmation relies on reversed-phase high-performance liquid chromatography, often coupled to mass spectrometry for identity and purity assessment. Mass spectrometry distinguishes the intact molecule from truncation products and from oxidation or deamidation variants that share similar chromatographic retention. Immunoassays appear in some biological studies but can cross-react with related peptides, so they are weaker tools for identity work. Reported purity figures depend heavily on the gradient, detector, and integration method used, which complicates direct comparison between laboratories.
Research quantities of ipamorelin are typically distributed as a white to off-white lyophilized powder. The solid dissolves readily in water and in aqueous buffers, and stock solutions are commonly prepared in sterile water or a mildly acidic diluent. Adsorption to plastic and glass surfaces can reduce the concentration of very dilute solutions, so containers and transfer steps deserve attention when accurate concentrations matter. Reconstituted material is generally used promptly rather than held for extended periods.
Amphetamine is a potent psychostimulant of the phenethylamine class that is approved for the treatment of attention deficit hyperactivity disorder (ADHD) and narcolepsy. Amphetamine is also used off-label as a performance and cognitive enhancer, and recreationally as an aphrodisiac and euphoriant. Although it is a prescription medication in many countries, unauthorized possession and distribution of amphetamine is often tightly controlled due to the significant health risks associated with uncontrolled or heavy use. As a consequence, amphetamine is illegally manufactured in clandestine labs to be trafficked and sold to users. Based upon drug and drug precursor seizures worldwide, illicit amphetamine production and trafficking is much less prevalent than that of methamphetamine. The first pharmaceutical amphetamine was Benzedrine, a brand of inhalers used to treat a variety of conditions. Because the dextrorotary isomer has greater stimulant properties, Benzedrine was gradually discontinued in favor of formulations containing all or mostly dextroamphetamine. Presently, it is typically prescribed as mixed amphetamine salts, dextroamphetamine, and lisdexamfetamine. Amphetamine is a norepinephrine–dopamine releasing agent (NDRA). It enters neurons through dopamine and norepinephrine transporters and facilitates neurotransmitter efflux by activating TAAR1 and inhibiting VMAT2. At therapeutic doses, this causes emotional and cognitive effects such as euphoria, change in libido, increased arousal, and improved cognitive control.
Solomon campaigned for subsidised medical services, directly influencing the Labour concept of the welfare state and the creation of the British National Health Service in 1948 Muriel Spark, novelist (Jewish father, possible Jewish mother; converted to Catholicism later in life) Bob Stanley (born Robert Andrew Shukman; 25 December 1964); musician, journalist, author, film producer; member of indie pop group Saint Etienne and music journalist for NME, Melody Maker, Mojo, The Guardian and The Times, as well as writing three books on music and football; also has a career as a DJ and as a producer of record labels, and has collaborated on a series of films about London. His second publication, Yeah! Yeah! Yeah!: The Story of Modern Pop, published by Faber & Faber; third publication Let's Do It: The Birth of Pop Music: A History, published by Pegasus. George Steiner, FBA (April 23, 1929 – February 3, 2020) author, literary critic, essayist, philosopher, novelist and educator; wrote about relationship between language, literature and society, as well as impact of the Holocaust; ranked "among the great minds in today's literary world"; was Professor University of Geneva (1974–94), Professor of Comparative Literature and Fellow in the University of Oxford (1994–95), Professor of Poetry in Harvard University (2001–02) and Fellow of Churchill College, Cambridge.
== History == LigoLab was co-founded in 2006 by Suren Avunjian and Edward Kharatian. Prior to founding LigoLab, Avunjian was Director of IT for Health Line Clinical Laboratories, which was eventually acquired by Labcorp. In late 2019, LigoLab partnered with Washington-based lab Northwest Pathology to develop TestDirectly, a software tool for facilitating DTC COVID-19 testing during the COVID-19 pandemic. TestDirectly was officially released in April 2020. Since its release, TestDirectly has been used for mass testing by organizations such as the Washington State Department of Corrections and Illinois Department of Public Health. In March 2020, LigoLab also provided LIS (laboratory information system) support for laboratories in several states including California, New York, and Washington that were conducting high-volume COVID-19 tests. In this capacity, LigoLab integrated its LIS & RCM Operating Platform with multiple instruments for COVID-19 testing. LigoLab formed a partnership with Northwest Pathology and the Florida Department of Health through TestDirectly in June 2020. The partnership was formed to carry out COVID-19 testing on long-term care residents and staff in the state of Florida. LigoLab's LIS & RCM Operating Platform was used by clinical laboratory Atlas Genomics to detect the first case of the B.1.1.7 variant of SARS-CoV-2 in King County, Washington in February 2021. In March 2021, LigoLab added LIS functionality to its TestDirectly platform. As of November 2021, the company had 130 clinical laboratories in the United States in its network.
== Historical context == In 1992, Stephen Kent and Martina Schnölzer at The Scripps Research Institute developed the "Chemical Ligation" concept, the first practical method to covalently condense unprotected peptide segments; the key feature of chemical ligation is formation of an unnatural bond at the ligation site. Just two years later in 1994, Philip Dawson, Tom Muir and Stephen Kent reported "Native Chemical Ligation", an extension of the chemical ligation concept to the formation of a native amide ('peptide') bond after initial nucleophilic condensation formed a thioester-linked condensation product designed to spontaneously rearrange to the native amide bond at the ligation site. Theodor Wieland and coworkers had reported the S-to-N acyl shift as early as 1953, when the reaction of valine-thioester and cysteine amino acid in aqueous buffer was shown to yield the dipeptide valine-cysteine. The reaction proceeded through the intermediacy of a thioester containing the sulfur of the cysteine residue. However, Wieland's work did NOT lead to the development of the native chemical ligation reaction. Rather, the study of amino acid thioester reactions led Wieland and others to develop the 'active ester' method for the synthesis of protected peptide segments by conventional chemical methods carried out in organic solvents.
Sources: en.wikipedia.org
Brazilian painting emerged in the late 16th century, influenced by Baroque, Rococo, Neoclassicism, Romanticism, Realism, Modernism, Expressionism, Surrealism, Cubism and Abstracionism making it a major art style called Brazilian academic art. The French Artistic Mission arrived in Brazil in 1816 proposing the creation of an art academy modeled after the respected Académie des Beaux-Arts, with graduation courses both for artists and craftsmen for activities such as modeling, decorating, carpentry and others and bringing artists such as Jean-Baptiste Debret. Upon the creation of the Imperial Academy of Fine Arts, new artistic movements spread across the country during the 19th century and later the event called Modern Art Week broke with academic tradition in 1922 and started a nationalist trend which was influenced by modernist arts. Among the best-known Brazilian painters are Ricardo do Pilar and Manoel da Costa Ataíde (baroque and rococo), Victor Meirelles, Pedro Américo and Almeida Júnior (romanticism and realism), Anita Malfatti, Ismael Nery, Lasar Segall, Emiliano Di Cavalcanti, Vicente do Rego Monteiro, and Tarsila do Amaral (expressionism, surrealism and cubism), Aldo Bonadei, José Pancetti and Candido Portinari (modernism).
Eptifibatide (Integrilin, Millennium Pharmaceuticals, also co-promoted by Schering-Plough/Essex), is an antiplatelet drug of the glycoprotein IIb/IIIa inhibitor class. Eptifibatide is a cyclic heptapeptide derived from a disintegrin protein (P22827) found in the venom of the southeastern pygmy rattlesnake (Sistrurus miliarius barbouri). It belongs to the class of the arginine-glycine-aspartate-mimetics and reversibly binds to platelets. Eptifibatide has a short half-life. The drug is the third inhibitor of GPIIb/IIIa that has found broad acceptance after the specific antibody abciximab and the non-peptide tirofiban entered the global market.
Dirt received critical acclaim, and is considered by many critics and fans alike as the group's magnum opus. In a retrospective review, Steve Huey of AllMusic said "Dirt is Alice in Chains' major artistic statement and the closest they ever came to recording a flat-out masterpiece. It's a primal, sickening howl from the depths of Layne Staley's heroin addiction, and one of the most harrowing concept albums ever recorded. Not every song on Dirt is explicitly about heroin, but Jerry Cantrell's solo-written contributions (nearly half the album) effectively maintain the thematic coherence—nearly every song is imbued with the morbidity, self-disgust, and/or resignation of a self-aware yet powerless addict." Michael Christopher of PopMatters praised the album, stating, "The record wasn't celebratory by any means—but you'll be hard-pressed to find a more brutally truthful work laid down—and that's why it will always be one of the greatest records ever made." Chris Gill of Guitar World described Dirt as "huge and foreboding, yet eerie and intimate," as well as "sublimely dark and brutally honest." Don Kaye of Kerrang! described Dirt as "an unflinching, brutally truthful and, yes, fiercely rocking testimonial to human endurance." A writer for Pitchfork noted that the album made Alice in Chains "one of the most famous bands in the world." At the 1993 Grammy Awards, Dirt received a nomination for Best Hard Rock Performance.
== Entrepreneurship == Mrksich has been an active entrepreneur over the past twenty years. He co-founded SAMDI Tech in 2011, which uses his label-free assay technology to perform high throughput screens for pharmaceutical companies. SAMDI Tech entered into a partnership with Charles River Laboratories in 2018 and was purchased by CRL in 2023. Mrksich also co-founded WMR Biomedical in 2008, with George Whitesides and Carmichael Roberts to develop resorbable stent materials; this company was renamed Lyra Therapeutics and had an IPO in 2020 (NASDAQ LYRA) and has drug-eluting stents in clinical trials for ear, nose and throat disease, including chronic rhinosinusitis. Mrksich has recently founded ModuMab Therapeutics, which applies his megamolecule technology to creating antibody mimics for a broad range of diseases.
Anopheles arabiensis Patton, 1905 Anopheles bwambae White, 1985 Anopheles melas Theobald, 1903 Anopheles merus Dönitz, 1902 Anopheles quadriannulatus (Theobald, 1911) Anopheles gambiae Giles, 1902 sensu stricto (s.s.) Anopheles coluzzii Coetzee & Wilkerson in Coetzee et al., 2013 Anopheles amharicus Hunt, Wilkerson & Coetzee in Coetzee et al., 2013 The individual species of the complex are morphologically difficult to distinguish from each other, although it is possible for larvae and adult females. The species exhibit different behavioural traits. For example, Anopheles quadriannulatus is both a saltwater and mineralwater species. A. melas and A. merus are saltwater species, while the remainder are freshwater species. Anopheles quadriannulatus generally takes its blood meal from animals (zoophilic), whereas Anopheles gambiae sensu stricto generally feeds on humans, i.e. is considered anthropophilic. Identification to the individual species level using the molecular methods of Scott et al. (1993) can have important implications in subsequent control measures.
Sources: en.wikipedia.org
By 1913, Japan was producing 672 million pounds of yarn per year, becoming the world's fourth-largest exporter of cotton yarn. The first railway was opened between Tokyo and Yokohama in 1872. The railway system was rapidly developed throughout Japan well into the twentieth century. The introduction of railway transportation led to more efficient production due to the decrease in transport costs, allowing manufacturing firms to move into more populated interior regions of Japan in search for labor input. The railway also enabled newfound access to raw materials that had previously been too difficult or too costly to transport. There were at least two reasons for the speed of Japan's modernization: the employment of more than 3,000 foreign experts (called o-yatoi gaikokujin or 'hired foreigners') in a variety of specialist fields such as teaching foreign languages, science, engineering, the army and navy, among others; and the dispatch of many Japanese students overseas to Europe and America, based on the fifth and last article of the Charter Oath of 1868: 'Knowledge shall be sought throughout the world so as to strengthen the foundations of Imperial rule.' The process of modernization was closely monitored and heavily subsidized by the Meiji government, enhancing the power of the great zaibatsu conglomerate business firms such as Mitsui and Mitsubishi.
Tanzi, RE; Petrukhin, K; Chernov, I; Pellequer, JL; Wasco, W; Ross, B; Romano, DM; Brzustowicz, LM; Devoto, M; Peppercorn, J; Bush, AI; Sternlieb, I; Pirastu, M; Gusella, JF; Evgrafov, O; Penchaszadeh, GK; Honig, B; Edelman, IS; Soares, MB; Scheinberg, IH; Gilliam, TC (1993). "Identification of the Wilson's disease gene: A copper transporting ATPase with homology to the Menke's disease gene". Nature Genetics. 5 (4): 344–350. Bibcode:1993NaGen...5..344T. doi:10.1038/ng1293-344. PMID 8298641. S2CID 610188. Levy-Lahad, E; Wasco, W; Poorkaj, P; Romano, DM; Oshima Jm, Pettingell WH; Yu, C; Jondro, PD; Schmidt, SD; Wang, K; Crowley, AC; Fu, Y-H; Guenette, SY; Galas, D; Nemens, E; Wijsman, EM; Bird, TD; Schellenberg, GD; Tanzi, RE (1995). "Candidate gene for the chromosome 1 familial Alzheimer's disease locus". Science. 269 (5226): 973–977. Bibcode:1995Sci...269..973L. doi:10.1126/science.7638622. PMID 7638622. S2CID 27296868. Bertram, L; Blacker, D; Mullin, K; Keeney, D; Jones, J; Basu, S; Yhu, S; McInnis, M; Go, R; Vekrellis, K; Selkoe, D; Saunders, A; Tanzi, RE (2000). "Evidence for genetic linkage of Alzheimer's disease to chromosome 10q". Science. 290 (5500): 2302–2303. Bibcode:2000Sci...290.2302B. doi:10.1126/science.290.5500.2302. PMID 11125142. Bertram, L; Hiltunen, M; Parkinson, M; Ingelsson, M; Lange, C; Ramasamy, K; Mullin, K; Menon, R; Sampson, AJ; Hsiao, MY; Elliott, KJ; Moscarillo, T; Hyman, BT; Wagner, SL; Becker, KD; Blacker, D; Tanzi, RE (2005). "Family-based association between Alzheimer's disease and variants in UBQLN1". N. Engl. J. Med. 352 (9): 884–894.
In November 1941 Adorno followed Horkheimer to what Thomas Mann called "German California", setting up house in a Pacific Palisades neighborhood of German émigrés that included Bertolt Brecht and Schoenberg. Adorno arrived with a draft of his Philosophy of New Music, a dialectical critique of twelve-tone music that Adorno felt, while writing it, was a departure from the theory of art he had spent the previous decades elaborating. Horkheimer's reaction to the manuscript was wholly positive: "If I have ever in the whole of my life felt enthusiasm about anything, then I did on this occasion," he wrote after reading the manuscript. The two set about completing their joint work, which transformed from a book on dialectical logic to a rewriting of the history of rationality and the Enlightenment. First published in a small mimeographed edition in May 1944 as Philosophical Fragments, the text waited another three years before achieving book form when it was published with its definitive title, Dialectic of Enlightenment, by the Amsterdam publisher Querido Verlag. This "reflection on the destructive aspect of progress" proceeded through the chapters that treated rationality as both the liberation from and further domination of nature, interpretations of both Homer's Odyssey and the Marquis de Sade, and analyses of the culture industry and antisemitism. With their joint work completed, Adorno and Horkheimer turned their attention to studies on antisemitism and authoritarianism in collaboration with the Nevitt Sanford-led Public Opinion Study Group and the American Jewish Committee.
Alkyllithiums and aryllithiums may also react with N,N-disubstituted amides to give aldehydes and ketones, and symmetrical ketones by reacting with carbon monoxide. They thermally decompose to eliminate a β-hydrogen, producing alkenes and lithium hydride: another route is the reaction of ethers with alkyl- and aryllithiums that act as strong bases. In non-polar solvents, aryllithiums react as the carbanions they effectively are, turning carbon dioxide to aromatic carboxylic acids (ArCO2H) and aryl ketones to tertiary carbinols (Ar'2C(Ar)OH). Finally, they may be used to synthesise other organometallic compounds through metal-halogen exchange.
=== Plastics and building materials === In one large-scale application, melamine is combined with formaldehyde and other agents to produce melamine resins. Such resins are characteristically durable thermosetting plastic used in high-pressure decorative laminates such as Wilsonart, melamine dinnerware, laminate flooring, and dry erase boards. Melamine cookware is not microwave-safe, and can be identified from the fact it is "slightly heavier and noticeably thicker than its plastic counterparts." Melamine foam is used as insulation, soundproofing material and in polymeric cleaning products, such as Magic Eraser. Melamine is one of the major components in Pigment Yellow 150, a colorant in inks and plastics. Melamine also is used in the fabrication of melamine polysulfonate, used as a superplasticizer for making high-resistance concrete. Sulfonated melamine formaldehyde (SMF) is a polymer used as a cement admixture to reduce the water content in concrete while increasing the fluidity and the workability of the mix during handling and pouring. It results in concrete with a lower porosity and a higher mechanical strength, exhibiting an improved resistance to aggressive environments and a longer lifetime.
Sources: en.wikipedia.org
不是。它属于人工合成的五肽，设计上模拟胃饥饿素受体的部分作用，但不存在于人体天然激素谱中。
生长激素释放激素通过其专用受体起作用，而 ipamorelin 主要作用于胃饥饿素受体。两者可影响生长激素释放，但信号通路和下游效应并不相同。
研究多集中在生长激素释放的急性调节、受体选择性以及不同给药方式下的药代动力学。临床终点研究数量有限，长期结局尚不明确。
It is a synthetic pentapeptide in the growth hormone secretagogue family and acts as an agonist at the ghrelin receptor. It is handled as a laboratory research compound rather than a naturally occurring hormone.