pentapeptide comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-01-18. Where a claim depends on a specific study, the study is described rather than over-claimed.
Lyophilized material is generally stored cold and dry, with desiccant, and protected from light. In solution the peptide is more vulnerable: the histidine side chain can oxidize, and repeated freeze-thaw cycles promote aggregation and loss of material to container surfaces. A mildly acidic aqueous buffer is often used for short-term handling because it limits several degradation routes. Accurate prediction of long-term stability under a given set of conditions is difficult, and published stability data remain sparse.
Published discussion of this compound is uneven. Some references describe it as a tool for probing growth hormone regulation, while others focus on analytical characterization or on comparisons with related secretagogues. Statements about selectivity, half-life and potency often trace back to a small number of original reports that later authors cite secondhand. Readers evaluating a claim should therefore check whether a figure reflects a direct measurement or a repeated citation, and whether the underlying study was conducted in animals, in isolated cells or in human volunteers.
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。
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilized solid as supplied |
| Solubility | Freely soluble in water and polar solvents | Dissolution may require brief mixing |
| Typical storage temperature | Minus 20 degrees Celsius or below | Dry, desiccated, protected from light |
| Common analytical method | Reversed-phase HPLC with mass spectrometry | Purity plus identity confirmation |
| Common synonyms | Ipamorelin acetate, NNC 26-0161 | Research code used in early literature |
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.
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.
The compound was developed at Novo Nordisk during the 1990s as part of a programme seeking secretagogues with improved selectivity. It was described in the peer-reviewed literature in 1998 alongside related pentapeptides from the same series. Investigators advanced it because it raised growth hormone output in animal models while leaving other pituitary hormones comparatively unaffected. The development code NNC 26-0161 appears in earlier reports, and ipamorelin later became the common designation in published work.
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.
=== Singer-songwriter === In 1996, Sheik released his self-titled debut album, which was certified gold. The album featured the hit single "Barely Breathing", which peaked at number 16 and remained on the Billboard Hot 100 for 55 consecutive weeks. "Barely Breathing" also enjoyed Top 20 success on Adult Contemporary radio, reached No. 2 on the Adult Top 40 charts, and garnered Sheik a Grammy Award nomination for Best Male Pop Vocal Performance. In 1998, Sheik recorded "Embraceable You" for Red Hot + Rhapsody, a George Gershwin tribute, and also recorded "Songbird" for another tribute, Legacy: A Tribute to Fleetwood Mac's Rumours. Also in 1998, Sheik released Humming, which featured orchestral and string arrangements. Sheik sang a duet with singer Howard Jones on Jones' 2000 single entitled Someone You Need. He released Phantom Moon, a Nick Drake-influenced album created in collaboration with poet and playwright Steven Sater, in 2001. The following year, Sheik released Daylight, which included the singles "On a High" and "Half-Life". After a four-year recording break, Sheik released White Limousine (2006), which included a DVD allowing listeners to remix and reinterpret songs from the album. In 2009, he released Whisper House, a concept album which provided the score for the musical of the same name. The stage musical premiered at The Old Globe Theatre in San Diego in January 2010, after a workshop at Vassar College, produced by New York Stage and Film in 2009. In 2011, Sheik released Covers 80s, an album including covers of popular 1980s songs.
δDs of annual precipitation in different regions of the world are shown on the map. The precipitation is more D-enriched near the equator in the Tropics. The δDs generally fall in the range of around −30 ~ −150‰ in the northern hemisphere and −30~+30‰ over land areas of the southern hemisphere. In North America, the δD of average monthly precipitation across regions is lower in January (ranging up to around −300‰ in Canada) than in July (up to around −190‰). The overall mean precipitation is determined by the balance between evaporation of water from the oceans and other surface water and condensation of water vapor in the form of rain. Net evaporation should equal net precipitation, and the δD for precipitation is around −22‰ (global average). The Global Network of Isotopes in Precipitation (GNIP) investigates and monitors the isotopic composition of precipitation at various sites all over the world. The mean precipitation can be estimated by the equation, δ2H = 8.17(±0.07) δ18O + 11.27(±0.65)‰ VSMOW. (Rozanski et al., 1993) This equation is the slightly modified version from the general global meteoric water line (GMWL) equation, δ2H = 8.13δ18O + 10.8, which provides the average relationship between δ2H and δ18O of natural terrestrial waters.
Overcoming serious difficulties, President Suárez achieved these two objectives and the first free elections since 1936 could be held on June 15, 1977. Union of the Democratic Centre (UCD), the party organized by President Suárez, won the elections, although not by absolute majority, and sought the consensus of the rest of the political forces ─ and especially of the other great winner, the PSOE ─ to create the new legal framework that was to replace the fundamental laws of the Franco regime, as well as to face the economic crisis, the reappearance of the "regional question" and the increase of terrorism by ETA. This led to the creation of the political transition to democracy model, which was based on the Amnesty Law of 1977 that included everything that had happened during the Franco dictatorship ─ thus constituting a so-called "pact of oblivion" ─ and in the approval of a Consensus Constitution in exchange for the leftist parties abandoning their claim to establish the Republic. On December 6, 1978, the referendum was held and the new democratic Constitution was approved. Once the Constitution was endorsed, President Suárez called elections for March 1979, which were won by UCD but again without an absolute majority. During the following two years, the governing party suffered an acute process of internal decomposition that culminated with the resignation of Adolfo Suárez in January 1981.
Sources: en.wikipedia.org
Penetrating abdominal trauma (PAT) typically arises from stabbings, ballistic injuries (shootings), or industrial accidents. PAT can be life-threatening because abdominal organs, especially those in the retroperitoneal space, can bleed profusely, and the space can hold a large volume of blood. If the pancreas is injured, it may be further injured by its own secretions, in a process called autodigestion. Injuries of the liver, common because of the size and location of the organ, present a serious risk for shock because the liver tissue is delicate and has a large blood supply and capacity. The intestines, taking a large part of the lower abdomen, are also at risk of perforation. People with penetrating abdominal trauma may have signs of hypovolemic shock (insufficient blood in the circulatory system) and peritonitis (an inflammation of the peritoneum, the membrane that lines the abdominal cavity). Penetration may abolish or diminish bowel sounds due to bleeding, infection, and irritation, and injuries to arteries may cause bruits (a distinctive sound similar to heart murmurs) to be audible. Percussion of the abdomen may reveal hyperresonance (indicating air in the abdominal cavity) or dullness (indicating a buildup of blood). The abdomen may be distended or tender, signs which indicate an urgent need for surgery. The standard management of penetrating abdominal trauma was for many years mandatory laparotomy.
Within two years, they had opened 29 stores in Singapore and Malaysia, almost as many stores as the Hymans had opened in their 35 years of ownership. In 1998, the Sassoons, along with longtime friend Severin Wunderman, purchased the parent company, International Coffee & Tea LLC, from the Hymans, and took it global. Victor Sassoon worked out of Singapore, Sunny Sassoon worked in Los Angeles, and Wunderman was a silent partner with no role in management. International Coffee & Tea, LLC remained the name of the holding company. Sunny Sassoon served as president and CEO from 1998 until 2009, when he moved to the executive chairman position until 2019. In 2009, Mel Elias (Sassoon's brother-in-law) assumed the role of president and CEO of the company, after spending seven years as chief operating officer. In September 2013, a significant equity position in Coffee Bean was acquired from International Coffee & Tea by US-based Advent International, in partnership with South Korea-based Mirae Asset Private Equity and Taiwan-based CDIB Capital. The Sassoon family remains a large shareholder. John Fuller served as president and CEO from 2015 to 2020. In April 28, 2014, Hyman died at the age of 82. He had heart disease. In 2019, the Philippines' Jollibee Foods Corporation (JFC) acquired The Coffee Bean & Tea Leaf for $350 million, making it Jollibee's biggest investment at the time. JFC bought it through Java Ventures LLC, a company from the US that is a wholly owned subsidiary of Super Magnificent Coffee Company Pte. Ltd. in Singapore, a subsidiary of Jollibee Worldwide Pte Ltd.
The new department was financed by a US $12-million gift from Bill Gates, who shared Hood's interest in combining biological research and computer technology and applying them to medical research. Roger Perlmutter, who had worked in Hood's lab at Caltech before moving to UW as chair of the immunology department, played a key role organizing his recruitment to UW. Hood and other scientists from Caltech's NSF center moved to the University of Washington during 1992-1994, where they received renewed support from the NSF as the Center for Molecular Biotechnology. (Later, in 2001, the department of molecular biotechnology and the genetics department at UW reorganized to form the department of genome sciences.) In 2000 Hood resigned his position at the University of Washington to become co-founder and president of the non-profit Institute for Systems Biology (ISB), possibly the first independent systems biology organization. His co-founders were protein chemist Ruedi Aebersold and immunologist Alan Aderem. Hood is still an affiliate professor at the University of Washington in Computer Science, Bioengineering and Immunology. In April 2017, the ISB announced that Hood will be succeeded as president of ISB as of January 2018 by James Heath, while continuing to lead his research group at ISB and serving on ISB's board of directors. Hood believes that a combination of big data and systems biology has the potential to revolutionize healthcare and create a proactive medical approach focused on maximizing the wellness of the individual. He coined the term "P4 medicine" in 2003.
=== Preparation of acyl cyanides === Acyl cyanides (α-oxonitriles) can in certain cases be prepared by reacting carboxylic acid halides with transition metal cyanides (e.g., copper cyanide or silver cyanide). This approach is particularly effective for aromatic carboxylic acid halides and aliphatic acyl bromides, whereas aliphatic acyl chlorides are unreactive. Aliphatic acyl cyanides can instead be synthesized by reacting carboxylic acid chlorides with trimethylsilyl cyanide.
Sources: en.wikipedia.org
Reversed-phase liquid chromatography is standard for purity, and mass spectrometry is standard for identity. Amino acid analysis is used when quantitative composition matters. No single technique answers every question, so laboratories usually combine two or three.
The peptide contains aromatic and imidazole groups that absorb ultraviolet light and can participate in photo-induced reactions. Those reactions can alter the molecule or generate new species. Amber glass or opaque packaging reduces the exposure.
Long-term stability data across many temperature and humidity conditions are limited. Most guidance is extrapolated from short studies on related peptides. The effect of repeated handling on a specific lot is generally not characterized.
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。