Everything below concerns selectivity. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-02-21. Numbers and descriptions here follow the published literature rather than marketing material.
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。
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。
At the receptor level, ipamorelin binds GHS-R1a and triggers signaling through Gq-coupled pathways. Activation leads to calcium release and downstream effects in pituitary somatotroph cells. These events promote the release of growth hormone into circulation. The response depends on the presence of the receptor and on the physiological state of the animal or tissue studied. Because the receptor is also found in other tissues, effects beyond the pituitary have been examined in laboratory models, though the extent of those effects remains an area of ongoing study.
One distinguishing feature reported in animal studies is selectivity. Ipamorelin stimulated growth hormone release with limited elevation of adrenocorticotropic hormone or cortisol compared with earlier secretagogues such as GHRP-6. This pattern has been described as more selective for the growth hormone axis. The finding comes mainly from preclinical work, and the degree to which it holds across species and doses is not fully settled. Reports also describe effects on gastric motility in animal models, suggesting activity outside the pituitary, though the clinical relevance of this observation is uncertain.
| 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 |
Selectivity is the property most often attached to this peptide. Published animal and early human studies record increases in growth hormone release after administration, with adrenocorticotropic hormone and cortisol responses remaining small by comparison. Effects on appetite-related pathways also appear weaker than those reported for several earlier secretagogues. Reviews that compare members of the growth hormone secretagogue family cite these findings frequently, though the receptor-level explanation for the selectivity continues to be debated rather than settled.
Ipamorelin is a synthetic pentapeptide classified as a growth hormone secretagogue. Its sequence, Aib-His-D-2-Nal-D-Phe-Lys-NH2, combines three non-proteinogenic residues with a C-terminal amide. The N-terminal aminoisobutyric acid unit and the two aromatic D-amino acids distinguish it from peptides assembled only from standard L-amino acids. Its formula is C38H49N9O5, corresponding to an average mass near 711.9 Da. At neutral pH the molecule carries a net positive charge, a property that shapes its behaviour in chromatographic and electrophoretic systems.
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。
现有文献多来自小规模、短期的研究，涉及生长激素缺乏、术后肠麻痹等方向。长期使用是否导致受体脱敏，以及重复给药后效应是否衰减，仍属开放问题。不同研究之间的剂量、给药途径和受试者特征差异较大，因此结论外推需谨慎。关于临床获益的确切证据尚不充分，需要更大规模的对照试验来澄清。
In 1899 he was appointed assistant professor at West Virginia University. He moved to the McLean Hospital Boston in 1900 as a research biochemist, eventually moving to Harvard Medical School in 1907 as an associate professor of biological chemistry, becoming the Hamilton Kuhn Professor of Biological Chemistry and Molecular Pharmacology in 1909. Together with Vintilă Ciocâlteu Otto Folin designed the Folin-Ciocalteu reagent to detect polyphenols. In 1920, he co-developed with Hsien Wu the Folin-Wu method of assaying glucose in protein-free filtrates of blood. Folin was elected the president of the American Society of Biological Chemists (now the American Society for Biochemistry and Molecular Biology) in 1909. He was a member of the editorial board of the Journal of Biological Chemistry. He was elected to the National Academy of Sciences and was awarded the Carl Wilhelm Scheele Medal of the Swedish Chemical Society in 1930.
John E. Macor is an American medicinal chemist known for his contributions to drug discovery in neuroscience and other therapeutic areas. He is a co-inventor of four drugs approved by the U.S. Food and Drug Administration (FDA): the migraine treatments eletriptan (Relpax), rimegepant (Nurtec ODT), and zavegepant (Zavzpret), and sparsentan (Filspari), a treatment for IgA nephropathy. In 2014, he was inducted into the Hall of Fame of the American Chemical Society’s Division of Medicinal Chemistry. Macor currently works at Babylon Biosciences, a San Francisco-based startup focused on treatments for Alzheimer's disease.
The system draws water from below into the material. The water diffuses into the higher layer, where it evaporates, leaving behind any contaminants. The vapor condenses on top, where it can be captured. The film is produced by repeatedly adding a fluid coating that hardens. Bacteria produce nanocellulose fibers with interspersed graphene oxide flakes. The film is light and easily manufactured at scale.
Target identification provides resources important for searching drug targets with information on genome annotation, proteome annotation, potential targets, and protein structure. Virtual screening compiles resources important for virtual screening as QSAR techniques, docking QSAR, cheminformatics, and siRNA/miRNA. Drug design provides resources important for designing drug inhibitors/molecules, such as lead optimization, pharmacoinformatic, ADMET, and clinical informatics.
Sources: en.wikipedia.org
== Substrate depletion == In 2022, it was discovered that aminoacyl-tRNA synthetases may incorporate alternative amino acids during shortages of their precursors. In particular, tryptophanyl-tRNA synthetase (WARS1) will incorporate phenylalanine during tryptophan depletion, essentially inducing a W>F codon reassignment. Depletion of the other substrate of aminoacyl-tRNA synthetases, the cognate tRNA, may be relevant to certain diseases, e.g. Charcot–Marie–Tooth disease. It was shown that CMT-mutant glycyl-tRNA synthetase variants are still able to bind tRNAGly but fail to release it, leading to depletion of the cellular pool of glycyl-tRNAGly, what in turn results in stalling of the ribosome on glycine codons during mRNA translation.
Allison and Tasuku Honjo received the Nobel Prize in Physiology or Medicine for their discovery of cancer therapy by inhibition of negative immune regulation, using monoclonal antibodies that prevent inhibitory linkages. The translational work needed to implement these ideas is credited to Lee Nadler. As explained in an NIH article, "He was the first to discover monoclonal antibodies directed against human B-cell–specific antigens and, in fact, all the known human B-cell–specific antigens were discovered in his laboratory. He is a true translational investigator, since he used these monoclonal antibodies to classify human B-cell leukemia and lymphomas as well as to create therapeutic agents for patients. [...] More importantly, he was the first in the world to administer a monoclonal antibody to a human (a patient with B-cell lymphoma)."
They had planned to wed in summer 2020 but postponed the event twice due to the COVID-19 pandemic. At her wedding, Alizée wore the 1980s wedding dress belonging to Carole Middleton, her mother-in-law. The couple welcomed their first child, Inigo Gabriel, on 21 September 2023.
=== Analogues === Analogues of 4-HO-MET include psilocin (4-HO-DMT), 4-HO-DET (ethocin), 4-HO-MiPT (miprocin), 4-HO-DPT (deprocin), 4-HO-MPT (meprocin), 4-HO-DALT (dalocin), and 4-HO-MALT (malocin), among others. 4-AcO-MET (metacetin) and 4-PrO-MET are ester prodrugs of 4-HO-MET. Other analogues of 4-HO-MET include methylethyltryptamine (MET), 5-HO-MET, and 5-MeO-MET.
Galloway's comments were criticised by anti-rape campaigners as "ignorant", "very unhelpful", "offensive" and "deeply concerning." Then-Respect Party leader Salma Yaqoob described Galloway's comments as "deeply disappointing and wrong." She subsequently resigned from her post and the party. Yaqoob later stated that having to choose between Galloway's "anti-imperialist stances" and standing up for the rights of women was "a false choice." Galloway subsequently lost his job as a columnist for Holyrood, a Scottish political magazine, for refusing to apologise for his remarks, and subject to a No platform policy by the National Union of Students.
Sources: en.wikipedia.org
Bukele registered as a presidential pre-candidate on 26 June 2023 with Nuevas Ideas; Ulloa registered as Bukele's vice-presidential pre-candidate. Nuevas Ideas nominated Bukele and Ulloa as their presidential and vice-presidential candidates on 9 July. The party began registering Bukele and Ulloa's candidacies with the TSE on 26 October, the last day to do so. On 3 November 2023, the TSE registered their candidacies amidst opposition requests to reject Bukele's candidacy. On 30 November 2023, the Legislative Assembly granted Bukele and Ulloa leaves of absence to focus on their re-election campaign. The leave went into effect the following day and Bukele's presidential powers were suspended. The Legislative Assembly named Claudia Rodríguez de Guevara, Bukele's presidential secretary, as the presidential designate; Rodríguez was the first woman in Salvadoran history to hold presidential power. Her appointment was criticized by some lawyers and opposition politicians as unconstitutional. Including Bukele, there were six presidential candidates in the 2024 election. His primary opponents were ARENA's Joel Sánchez, a businessman, and the FMLN's Manuel Flores, a former legislator. Bukele led Sánchez and Flores by large margins in opinion polling before the election. Bukele promised to maintain the gang crackdown, invest in infrastructure projects, and promote economic growth during his second term. On 4 February 2024, he won re-election with 84.65 percent of the vote. Bukele was the first Salvadoran president to be re-elected since Maximiliano Hernández Martínez in 1944.
As an expansion pack for Half-Life, Opposing Force is a first-person shooter. The overall gameplay of Opposing Force does not significantly differ from that of Half-Life. Players navigate through levels, fight hostile non-player characters and solve a variety of puzzles to advance. The game continues Half-Life's methods of an unbroken narrative. The player sees everything through the first person perspective of the protagonist and remains in control of the player character for almost all of the game. Story events are conveyed through the use of scripted sequences rather than cut scenes. Progress through the world is continuous; although the game is divided up into chapters, the only significant pauses are when the game needs to load the next part of an environment. Opposing Force also features an extended multiplayer, incorporating the various new environments and weapons into the original deathmatch mode used in Half-Life. After release, a new capture the flag mode with additional levels, items and powerups, was created by Gearbox. For the most part the player battles through the single-player game alone, but is occasionally assisted by friendly non-player characters. Security guards and scientists will occasionally help the player in reaching new areas and convey relevant plot information. However, Opposing Force also features fellow U.S. Marines who will assist the player in combat to a far greater degree than security guards.
==== Precipitation amount effect ==== In contrast to temperature control at high latitudes, the isotopic composition of precipitation in the tropics is mainly influenced by rainfall amount (negative correlation). This "amount effect" is also observed for summer precipitation in the subtropics. Willi Dansgaard, who first proposed the term "amount effect", suggested several possible reasons for the correlation: (1) As cooling and condensation progress, the rainfall isotopic composition reflects an integrated isotopic depletion by the Rayleigh process; (2) A small amount of rainfall is more likely to be influenced by evaporation and exchange with surrounding moisture, which tend to make it more isotopically enriched. At low latitudes, the amount effect for δ18O is around −1.6‰/100mm precipitation increase at island stations, and −2.0‰/100mm at continental stations. It was also noted that the amount effect was most pronounced when comparing isotopic composition of monthly precipitation at different places in the tropics. The amount effect is also expected for HIC, but there are not as many calibration studies. Across southeast Asia, the δD sensitivity to monthly precipitation amount varies between −15 and −25‰/100mm depending on location. In temperate regions, the isotopic composition of precipitation is dominated by rainfall amount in summer, but more controlled by temperature in the winter. The amount effect may also be complicated by changes in regional moisture sources.
Carod left the government after acknowledging that the meeting with ETA had taken place, but affirming that he had not negotiated anything, least of all a truce restricted to Catalonia. However, a few days later ETA declared a truce "only for Catalonia with effect from January 1, 2004."
Sources: en.wikipedia.org
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。