This is a working overview of 五肽, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-07-09. Anything still debated is marked as such rather than presented as settled.
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.
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。
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic pentapeptide | Growth hormone secretagogue family |
| Molecular mass | Approximately 711.9 Da | Free base, calculated value |
| Receptor target | GHS-R1a, the ghrelin receptor | Agonist activity reported |
| Sequence | Aib-His-D-2-Nal-D-Phe-Lys-NH2 | C-terminal amide |
| Reported selectivity | Little change in ACTH, cortisol, prolactin | Based mainly on animal data |
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.
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.
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.
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。
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。
Lyophilized material is generally stored frozen and protected from light and moisture. Typical recommendations place dry powder at temperatures well below freezing, while reconstituted solutions are kept cold and used within a defined window. Repeated freezing and thawing should be avoided because it can promote aggregation and loss of material. The choice of solvent matters as well; compatibility with the intended diluent should be checked before preparation. These handling practices aim to preserve both the quantity and the integrity of the peptide.
Verification of identity and purity relies on analytical methods used across peptide chemistry. Reverse-phase high-performance liquid chromatography separates components by hydrophobicity and provides a purity estimate. Mass spectrometry confirms molecular mass and helps detect modifications. Together these techniques give complementary information about whether a sample matches its expected structure. Results depend on method parameters and reference standards, so reported purity values are meaningful only when the analytical conditions are stated. Consistency between laboratories requires comparable protocols and well-characterized reference materials.
=== Legal status === THC, along with its double bond isomers and their stereoisomers, is one of only three cannabinoids scheduled by the UN Convention on Psychotropic Substances (the other two are dimethylheptylpyran and parahexyl). It was listed under Schedule I in 1971, but reclassified to Schedule II in 1991 following a recommendation from the World Health Organization (WHO). Based on subsequent studies, the WHO has recommended the reclassification to the less-stringent Schedule III. Cannabis as a plant is scheduled by the Single Convention on Narcotic Drugs (Schedule I and IV). It is specifically still listed under Schedule I by US federal law under the Controlled Substances Act for having "no accepted medical use" and "lack of accepted safety". However, dronabinol, a pharmaceutical form of THC, has been approved by the FDA as an appetite stimulant for people with AIDS and an antiemetic for people receiving chemotherapy under the trade names Marinol and Syndros. In 2003, the WHO Expert Committee on Drug Dependence recommended transferring THC to Schedule IV of the convention, citing its medical uses and low abuse and addiction potential. In 2019, the Committee recommended transferring Δ9-THC to Schedule I of the Single Convention on Narcotic Drugs of 1961, but its recommendations were rejected by the United Nations Commission on Narcotic Drugs.
== L == LALLS – Low-angle laser light scattering LC-MS – Liquid chromatography-mass spectrometry LEED – Low-energy electron diffraction LEEM – Low-energy electron microscopy LEIS – Low-energy ion scattering LIBS – Laser induced breakdown spectroscopy LOES – Laser optical emission spectroscopy LS – Light (Raman) scattering
== History == LG CNS was founded in 1987 as System Technology Management (STM), a 50:50 joint venture between LG and Electronic Data Systems. In 1995, the company was renamed LG-EDS System as part of LG Group's corporate identity integration project. After LG acquired all of EDS's shares, the company changed its name to LG CNS in January 2002. In 2019, LG sold a 35% stake in LG CNS to Macquarie Group for 1 trillion won (US$865 million). This sale occurred amid growing criticism of South Korea's chaebols for allegedly benefiting founding families by over-relying on outsourcing contracts and directing work to subsidiaries and affiliates. Macquarie acquired the stake in LG CNS with the condition that LG would list the company by April 2025. As a result, LG CNS debuted on the market in February 2025. On January 28, 2026, Macquarie divested its remaining 8.3% stake in the company through a block deal.
According to the Indian naval hydrographic charts, the mainland coastline consists of 43% sandy beaches, 11% rocky shores including cliffs, and 46% mudflats or marshy shores. Coastal features include the marshy Rann of Kutch of western India and the alluvial Sundarbans delta of eastern India, the latter shared with Bangladesh. India has two archipelagos: the Lakshadweep coral atolls off the south-western coast, and the Andaman and Nicobar Islands, a volcanic chain in the Andaman Sea.
"Open surgery" is any surgical procedure where the incision made is enough to allow the surgery to take place. With tissues and structures exposed to the air, the procedure can be performed either with the unaided vision of the surgeon or with the use of loupes or microscopes. Some examples of open surgery used are for herniated disc commonly called a "slipped disc", and most types of cardiac surgery and neurosurgery.
Sources: en.wikipedia.org
Otamahan (おたまはん), developed by Yoshida Furusato Mura (a third-sector company) in Unnan, Shimane (launched 2002). Tamago ni kakeru oshōyu (たまごにかけるお醤油, Soy Sauce for Pouring on Egg), by Teraoka Yuki Jōzō in Fukuyama, Hiroshima. Tamago kake gohan ni kakeru shōyu (玉子かけご飯にかける醤油, Soy Sauce for Pouring on Tamago Kake Gohan), by Hamada Shōyu in Kumamoto. Higeta Tamago kake gohan ni dōzo! (ヒゲタ たまごかけご飯にどうぞ!, Higeta - Please Use for Tamago Kake Gohan!), by Higeta Shōyu in Choshi, Chiba. Tamago ni kakeru dashi shōyu (たまごにかけるだし醤油, Dashi Soy Sauce for Pouring on Egg), by Igagoe Co., Ltd. in Iga, Mie. Kaketarō (かけたろう), by Jinushi Kyōwa Shōkai / Kokekokkō Republic in Taki, Mie. Additionally, specialized furikake seasonings specifically for TKG are also available. Bull-Dog Sauce produced a seasoning mix called Ouchi de Gyūdon-fū Tamago Kake Gohan (おうちで 牛丼風 たまごかけご飯, Gyūdon-Style Tamago Kake Gohan at Home).
====== Stimulation of beta-defensin production ====== SeV is a very effective stimulant of expression of human beta-defensin-1 (hBD-1). This protein is a member of the beta-defensin family of proteins that bridges innate and adaptive immune responses to a pathogen infection. In response to SeV infection, the production of hBD-1 mRNA and protein increases 2 hours after exposure to the virus in purified plasmacytoid dendritic cells or in PBMC.
== Education and career == Flegg received her PhD in Applied Mathematics from Queensland University of Technology in 2009. Her dissertation, "Mathematical Modelling of Chronic Wound Healing", was supervised by Dr. Sean McElwain. From 2010 to 2013, she was a researcher at the University of Oxford developing mathematical models for the spread of resistance to antimalarial drugs. From 2014 to early 2017, she was a mathematical lecturer in the School of Mathematical Sciences at Monash University. In May 2017, she joined the School of Mathematics and Statistics at the University of Melbourne as a senior lecturer in Applied Mathematics and was promoted to associate professor in 2020 and again to Professor in 2022. Flegg is an expert in the field of mathematical biology, with special focus in infectious disease epidemiology, wound healing and tumor growth. As of 2020, Flegg also serves as an editorial board member for PLOS Computational Biology, eLife and the Bulletin of Mathematical Biology.
=== Involved subunits === The substrate is coordinated to the zinc and this enzyme has two zinc atoms per subunit. One is the active site, which is involved in catalysis. In the active site, the ligands are Cys-46, Cys-174, His-67, and one water molecule. The other subunit is involved with structure. In this mechanism, the hydride from the alcohol goes to NAD+. Crystal structures indicate that the His-51 deprotonates the nicotinamide ribose, which deprotonates Ser-48. Finally, Ser-48 deprotonates the alcohol, making it an aldehyde. From a mechanistic perspective, if the enzyme adds hydride to the re face of NAD+, the resulting hydrogen is incorporated into the pro-R position. Enzymes that add hydride to the re face are deemed Class A dehydrogenases.
Sources: en.wikipedia.org
Ipamorelin is a synthetic pentapeptide that stimulates growth hormone release by activating the ghrelin receptor. It is handled as a research tool rather than as a licensed therapeutic product. Its short chain length makes it comparatively simple to synthesize and analyze.
Both bind the same receptor, but ghrelin is a 28-amino-acid hormone with roles in appetite and energy balance. Ipamorelin is a much smaller synthetic peptide selected for growth hormone release with limited effect on appetite signaling in animal models. The full overlap between their effects is not completely mapped.
Most published data come from animal studies and a small number of human trials. Findings on growth hormone release are reasonably consistent, while long-term effects and direct comparisons with other secretagogues remain incompletely studied. Open questions include duration of action across different populations.
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。