Everything below concerns ipamorelin. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-08-01. Numbers and descriptions here follow the published literature rather than marketing material.
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。
在 GHS 家族中，早期肽类如 GHRP-6 与 GHRP-2 会同时促进生长激素、皮质醇与催乳素的释放，并明显增加食欲。Ipamorelin 在动物与早期人体研究中表现出对生长激素释放的相对选择性，对上述其他激素的影响较小。这种差异通常归因于受体结合模式与下游信号偏向的不同，而完整的分子解释仍有待补充。需要区分的是，选择性是研究观察中的相对程度，并非绝对界限。
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。
Selectivity distinguishes ipamorelin from first-generation secretagogues such as GHRP-6. At doses that reliably raise growth hormone, it shows little stimulation of adrenocorticotropic hormone or cortisol release in animal models, and it does not markedly raise prolactin or appetite. Binding at GHS-R1a on pituitary somatotrophs triggers calcium influx and pulsatile growth hormone secretion. Because the compound mimics the natural ghrelin signal, the release pattern tends to follow the body's own rhythm rather than producing a sustained elevation.
Most published work on ipamorelin comes from rodent studies and small early-phase human trials. Subcutaneous and intravenous routes have been used, while oral delivery is limited by poor absorption and rapid breakdown in the gut. The reported plasma half-life is short, on the order of two hours, and varies with species and assay method. Whether chronic use produces meaningful clinical benefit remains unresolved, and long-term safety data in humans are sparse. No major regulatory agency has approved the compound as a therapeutic drug.
| Property | Value | Notes |
|---|---|---|
| 分子式 | C38H49N9O5 | 五肽，C 端酰胺化 |
| 分子量 | 约 711.85 g/mol | 游离碱形式 |
| 外观 | 白色至类白色冻干粉 | 研究用材料的常见形态 |
| 溶解性 | 溶于水及 DMSO 等极性溶剂 | 建议现配现用 |
| 储存温度 | -20 °C 或更低 | 干燥、避光、限制冻融次数 |
Ipamorelin is a synthetic pentapeptide that belongs to the growth hormone secretagogue class. It acts as an agonist at the ghrelin receptor, also called the growth hormone secretagogue receptor type 1a. The compound was designed in the 1990s during a search for agents that release growth hormone with fewer off-target hormonal effects than earlier secretagogues. It appears in the research literature under several sequence-based names. Material supplied for laboratory work is normally a lyophilized solid, and it is not marketed as an approved therapeutic in major jurisdictions.
The molecule contains five residues, including alpha-aminoisobutyric acid, D-2-naphthylalanine, and D-phenylalanine, and it ends in a lysine amide. Non-natural and D-configured residues make the chain less susceptible to common peptidases, which helps explain its resistance to rapid breakdown. Its molecular formula is C38H49N9O5, corresponding to a free-base mass near 711.9 daltons. The C-terminal amide removes a negative charge and is a recurring feature in receptor-active peptides of this family. These structural choices are usually discussed as the basis for its selectivity profile.
Published animal and early human work describes growth hormone release that is separated from comparable rises in adrenocorticotropic hormone and cortisol. Prolactin changes are reported as small in the same studies. Selectivity is attributed to binding at the ghrelin receptor and to the downstream signaling that follows, rather than to differences in how quickly the peptide is cleared. Authors commonly label the compound selective rather than potent, because the same mass produces a smaller growth hormone response than some older secretagogues tested in parallel. Whether that profile holds across species and routes of administration remains an open question.
At the cellular level, ipamorelin binds the growth hormone secretagogue receptor, also called the ghrelin receptor. Activation of this receptor on pituitary somatotroph cells triggers a signaling cascade that leads to release of growth hormone into circulation. Because release follows a pulsatile pattern, studies often report peak concentration and total area under the curve rather than a single time point. Selectivity for this receptor is the property most frequently discussed in comparative work.
Compared with older secretagogues such as hexarelin or GHRP-6, ipamorelin shows weaker stimulation of cortisol, prolactin, and appetite in the animal models used for early characterization. Whether that selectivity is preserved across longer human exposures remains an open question, because published clinical data are limited in size and duration. Reported effects on food intake are generally described as modest. The compound is therefore treated in the literature as a relatively selective research tool rather than a fully characterized therapeutic agent.
Compared with earlier growth hormone secretagogues such as GHRP-6 and hexarelin, ipamorelin has been reported to produce less stimulation of adrenocorticotropic hormone, cortisol, and prolactin in animal and early human studies. This selectivity is usually attributed to differences in receptor subtype interactions and to the tissue distribution of the receptor. Effects on appetite appear weaker than those of ghrelin itself, although the supporting evidence base is small. Whether these differences produce a distinct clinical profile remains an open question, since controlled human trials are limited.
Ipamorelin is a synthetic pentapeptide first described in the 1990s by researchers at Novo Nordisk during a program to develop selective growth hormone secretagogues. Its sequence is Aib-His-D-2-Nal-D-Phe-Lys-NH2, incorporating two non-natural residues, alpha-aminoisobutyric acid and D-2-naphthylalanine. The C-terminus is amidated, and the material is supplied as a white lyophilized powder. The molecular formula is C38H49N9O5 and the monoisotopic mass is approximately 711.85 daltons. The short chain and modified residues give it greater resistance to enzymatic degradation than many larger peptide hormones.
For decades after Libby performed the first radiocarbon dating experiments, the only way to measure the 14C in a sample was to detect the radioactive decay of individual carbon atoms. In this approach, what is measured is the activity, in number of decay events per unit mass per time period, of the sample. This method is also known as "beta counting", because it is the beta particles emitted by the decaying 14C atoms that are detected. In the late 1970s an alternative approach became available: directly counting the number of 14C and 12C atoms in a given sample, via accelerator mass spectrometry, usually referred to as AMS. AMS counts the 14C/12C ratio directly, instead of the activity of the sample, but measurements of activity and 14C/12C ratio can be converted into each other exactly. For some time, beta counting methods were more accurate than AMS, but AMS is now more accurate and has become the method of choice for radiocarbon measurements. In addition to improved accuracy, AMS has two further significant advantages over beta counting: it can perform accurate testing on samples much too small for beta counting, and it is much faster – an accuracy of 1% can be achieved in minutes with AMS, which is far quicker than would be achievable with the older technology.
== Battery designs and formats == Lithium-ion batteries may have multiple levels of structure. Small batteries consist of a single battery cell. Larger batteries connect cells in parallel into a module and connect modules in series and parallel into a pack. Multiple packs may be connected in series to increase the voltage. Batteries may be equipped with temperature sensors, heating/cooling systems, voltage regulator circuits, voltage taps, and charge-state monitors. These components address safety risks like overheating and short circuiting.
Unione Sportiva Milanese was founded on 16 January 1902 as a multi-sports club, for compete in different disciplines, by Ambrogio Ferrario, Romolo Buni and Gilbert Marley at the Caffè Verdi in Porta Nuova in Milan. In the spring of 1904 the football section was established on the initiative of some footballers and gymnasts who left first A.C. Milan and then Mediolanum (among of which Umberto Meazza), while the affiliation to the Italian Football Federation (FIF), the current FIGC, took place in 1905. The shirt was black and white checked, with white shorts and black socks. Red and white were the colors of the second jersey. By virtue of this choice, against the current compared to the norm of the others teams, were nicknamed "Gli Scacchi" (the chessmen). At the end of the 1927-1928 championship, U.S. Milanese was automatically promoted to the National Division but was also forced by the fascist regime to merge with the Internazionale in the new Società Sportiva Ambrosiana, whose management was appointed Ernesto Torrusio, president of U.S. Milanese at the time, in favor of the fact that the registration number used to register for the championship was precisely that of U.S. Milanese. For two years the S.S. Ambrosiana celebrated the U.S. Milanese using its historic logo and the black and white checkered collar: S.S. Ambrosiana won the Italian football championship in 1929/30 season. 1932 saw the end of the merger with Internazionale and the reconstitution of U.S. Milanese, which was reborn only as a sports club without the football section. In 1945 U.S.
== Structure == The duodenum and the jejunum are the first and second parts of the small intestine, respectively. The suspensory muscle of the duodenum marks their formal division. The suspensory muscle arises from the right crus of the diaphragm as it passes around the esophagus, continues as connective tissue around the stems of the celiac artery and superior mesenteric artery, passes behind the pancreas, and enters the upper part of the mesentery, inserting into the junction between the duodenum and jejunum, the duodenojejunal flexure. Here, the muscles are continuous with the muscular layers of the duodenum.
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radioligands) have been developed for PET that are ligands for specific neuroreceptor subtypes such as [11C]raclopride, [18F]fallypride and [18F]desmethoxyfallypride for dopamine D2/D3 receptors; [11C]McN5652 and [11C]DASB for serotonin transporters; [18F]mefway for serotonin 5HT1A receptors; and [18F]nifene for nicotinic acetylcholine receptors or enzyme substrates (e.g. 6-FDOPA for the AADC enzyme). These agents permit the visualization of neuroreceptor pools in the context of a plurality of neuropsychiatric and neurologic illnesses. PET may also be used for the diagnosis of hippocampal sclerosis, which causes epilepsy. FDG, and the less common tracers flumazenil and MPPF have been explored for this purpose. If the sclerosis is unilateral (right hippocampus or left hippocampus), FDG uptake can be compared with the healthy side. Even if the diagnosis is difficult with MRI, it may be diagnosed with PET. The development of a number of novel probes for non-invasive, in-vivo PET imaging of neuroaggregate in human brain has brought amyloid imaging close to clinical use. The earliest amyloid imaging probes included [18F]FDDNP, developed at the University of California, Los Angeles, and Pittsburgh compound B (PiB), developed at the University of Pittsburgh. These probes permit the visualization of amyloid plaques in the brains of Alzheimer's patients and could assist clinicians in making a positive clinical diagnosis of Alzheimer's disease pre-mortem and aid in the development of novel anti-amyloid therapies.
Due to its broad availability, speed, and relatively low cost, it continues to be a common first-line tool in radiologic evaluation. Despite advances in CT, MRI, and other imaging techniques, there are many conditions in which traditional radiographs remain helpful in diagnosis. These include arthritis, pneumonia, bone tumors, fractures, congenital skeletal anomalies, and certain types of kidney stones. Mammography and DXA are two applications of low-energy projectional radiography, used for the evaluation of breast cancer and osteoporosis, respectively.
Systemic delivery into many cells in adult organisms can be accomplished by using covalent conjugates of Morpholino oligos with cell-penetrating peptides, and, while toxicity has been associated with moderate doses of the peptide conjugates, they have been used in vivo for effective oligo delivery at doses below those causing observed toxicity. An octa-guanidinium dendrimer attached to the end of a Morpholino can deliver the modified oligo (called a Vivo-Morpholino) from the blood to the cytosol. Delivery-enabled Morpholinos, such as peptide conjugates and Vivo-Morpholinos, show promise as therapeutics for viral and genetic diseases.
From the defeat of the Bohemian Revolt that collapsed at the 1620 Battle of White Mountain, the Habsburgs gradually integrated the Kingdom of Bohemia into their monarchy. During the subsequent Counter-Reformation, less populated areas were resettled with Catholic Germans from the Austrian lands. From 1627, the Habsburgs enforced the so-called Verneuerte Landesordnung ("Renewed Land's Constitution"), and one of its consequences was that German, according to mother tongue, gradually became the primary and official language, while Czech declined to a secondary role in the Empire. In 1749, the Austrian Empire enforced German as the official language again. Emperor Joseph II in 1780 renounced the coronation ceremony as Bohemian king and unsuccessfully tried to push German through as sole official language in all Habsburg lands (including Hungary). Nevertheless, German cultural influence grew stronger during the Age of Enlightenment and Weimar Classicism. Contrastingly, in the course of the Romanticism movement national tensions arose, both in the form of the Austroslavism ideology developed by Czech politicians like František Palacký and Pan-Germanist activist raising the German question. Conflicts between Czech and German nationalists emerged in the 19th century, for instance in the Revolutions of 1848: while the German-speaking population of Bohemia and Moravia wanted to participate in the building of a German nation state, the Czech-speaking population insisted on keeping Bohemia out of such plans.
Hospitalizations for suicide attempts are more frequent among women. In 2016, 47,110 women and 29,956 men were hospitalized following suicide attempts (61% women). In 2020, the figures were 47,826 women and 31,346 men (60.4% women). Suicidal ideation is also more common among women. In 2016, 5.4% of women and 4% of men reported suicidal thoughts; in 2020, the figures were 4.7% and 3.6%, respectively. Suicide mortality, however, is significantly higher among men. In 2016, 6,450 men and 1,985 women died by suicide (76% men). In 2020, there were 8,415 male and 2,790 female deaths by suicide (75% men).
Sources: en.wikipedia.org
=== Cardiac muscle === Cardiac muscle lies between the epicardium and the endocardium in the heart. Cardiac muscle cells generally only contain one nucleus, located in the central region. They contain many mitochondria and myoglobin. Unlike skeletal muscle, cardiac muscle cells are unicellular. These cells are connected to each other by intercalated disks, which contain gap junctions and desmosomes.
. This tensor may be expressed as the sum of the viscous stress tensor minus the hydrostatic pressure. The negative of the stress tensor is sometimes called the pressure tensor, but in the following, the term "pressure" will refer only to the scalar pressure. According to the theory of general relativity, pressure increases the strength of a gravitational field (see stress–energy tensor) and so adds to the mass-energy cause of gravity. This effect is unnoticeable at everyday pressures but is significant in neutron stars, although it has not been experimentally tested.
In obesity, a decreased sensitivity to leptin occurs (similar to insulin resistance in type 2 diabetes), resulting in an inability to detect satiety despite high energy stores and high levels of leptin.
The numbers 1.930 and 0.537 are phenomenological; these specific values provide a fairly good fit to the data. The product Re√fD (called the "friction Reynolds number") can be considered, like the Reynolds number, to be a (dimensionless) parameter of the flow: at fixed values of Re√fD, the friction factor is also fixed. In the Kármán–Prandtl resistance equation, fD can be expressed in closed form as an analytic function of Re through the use of the Lambert W function:
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两者都是 GHS-R1a 激动剂，但 ipamorelin 在研究中显示出更高的生长激素释放选择性。早期资料显示它对皮质醇、催乳素与食欲的刺激弱于 GHRP-6。这些差异是相对程度，而非绝对区分。
公开资料中它主要以研究用肽的形式出现，未获主要监管机构批准用于治疗。可得材料通常标注仅供研究使用。任何临床用途的宣称都缺少监管依据。
序列中的 Aib 与 D-2-Nal 等非天然残基可提高对肽酶的抵抗能力，并影响受体结合的构象。这类修饰在合成肽设计中较为常见。它们也使常规氨基酸分析需要额外步骤才能确认序列。
Aib 即 α-氨基异丁酸，是一种非蛋白质源氨基酸，其侧链为两个甲基。它在肽链中倾向于诱导螺旋构象并限制骨架的柔性。这种刚性被认为有助于抵抗蛋白酶切割。