pentapeptide raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-06-09 and is reviewed periodically as new material appears.
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.
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.
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, incorporating two non-natural residues that resist enzymatic breakdown. Researchers at Novo Nordisk described the compound in the 1990s while searching for agents that release growth hormone with fewer side effects than earlier secretagogues. The molecule acts as an agonist at the ghrelin receptor, also called GHS-R1a, which is expressed in the pituitary and in several peripheral tissues.
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 |
|---|---|---|
| Molecular formula | C38H49N9O5 | Pentapeptide with C-terminal amide |
| Average mass | Approximately 711.9 Da | Value derived from the formula |
| Appearance | White to off-white powder | Typically supplied as a lyophilised solid |
| Solubility | Soluble in water and aqueous acetonitrile | Dissolution aided by acidic diluents |
| Common synonyms | Ipamorelin; NNC 26-0161 | Code name used in early reports |
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.
At the molecular level, ipamorelin acts as an agonist at the growth hormone secretagogue receptor type 1a, the same G protein-coupled receptor that binds ghrelin. Receptor activation couples to Gq/11 signaling, raising intracellular calcium through inositol trisphosphate and diacylglycerol, which in turn promotes exocytosis of growth hormone from pituitary somatotroph cells. Ipamorelin binds this receptor with high affinity and shows weak activity at other secretagogue-related targets in vitro. Its action requires the intact receptor and is not reversed by growth hormone-releasing hormone antagonists.
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.
Identity and purity assessment for a research peptide of this kind typically combines reversed-phase high-performance liquid chromatography with mass spectrometry. The chromatographic run separates related impurities and yields a purity percentage, while electrospray ionization or matrix-assisted laser desorption mass spectrometry confirms the expected molecular mass. Amino acid analysis or tandem mass spectrometry sequencing can add confidence when material is intended for quantitative work. Laboratories differ in how they calculate and report purity, so figures from different sources are not always directly comparable.
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.
Peptides such as ipamorelin are subject to chemical and physical degradation. Hydrolysis of peptide bonds, oxidation of susceptible residues, and aggregation are common pathways that reduce purity over time. The rate of these processes depends on temperature, moisture, pH, and the number of freeze-thaw cycles a sample undergoes. Because the compound is typically handled as a lyophilized powder, controlling moisture during storage is a central concern. Degradation products can be detected with separation techniques that resolve the parent peptide from related impurities.
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.
active site Also binding site and catalytic site. The region of an enzyme to which one or more substrate molecules bind, causing the substrate or another molecule to undergo a chemical reaction. This region usually consists of one or more amino acid residues (commonly three or four) which, when the enzyme is folded properly, are able to form temporary chemical bonds with the atoms of the substrate molecule; it may also include one or more additional residues which, by interacting with the substrate, are able to catalyze a specific reaction involving the substrate. Though the active site constitutes only a small fraction of all the residues comprising the enzyme, its specificity for particular substrates and reactions is responsible for the enzyme's biological function.
=== Aftermath === In April 1864, the East Tennessee Union Convention reconvened in Knoxville, and while its delegates were badly divided, several, including Brownlow and Maynard, supported a resolution recognizing the Emancipation Proclamation. Confederate businessman Joseph Mabry and future business leaders such as Charles McClung McGhee and Peter Kern began working with Union leaders to rebuild the city. Brownlow remained vengeful, however, seizing the property of Confederate leaders J.G.M. Ramsey, William Sneed (including the Lamar House Hotel), and William Swan, and expelling known Confederate sympathizers from the city. Acts of Civil War-related violence occurred in Knoxville for years after the war. On September 4, 1865, Confederate soldier Abner Baker was lynched in Knoxville after killing a Union soldier who had killed his father. On July 10, 1868, Union major E.C. Camp shot and killed Confederate colonel Henry Ashby on Main Street in front of the courthouse over a Civil War grievance. On June 13, 1870, Joseph Mabry shot pro-Union attorney John Baxter in front of the Lamar House, capping a feud that had been building since the war. The following year, David Nelson, the son of pro-Union congressman T.A.R. Nelson, shot and killed Confederate general James Holt Clanton on Gay Street in front of the Lamar House.
Size of wound: Should be accurately measured at time of initial presentation and regularly remeasured until wound resolution. Wound location: Very useful consideration in many chronic wounds, such as diabetic foot ulcers, pressure ulcers, and venous ulcers. Acute wounds will be located in areas consistent with the mechanism of injury (e.g. diagonal chest wall bruising from seatbelt following car accident). Wound bed: A healthy wound bed will appear pink due to healthy granulation tissue. Presence of a dark red wound bed which bleeds easily on contact or excess granulation tissue (i.e. hypergranulation tissue) may indicate the presence of an infection or non-healing wound. Wound depth: The depth of a wound is often not apparent on visual inspection alone. Proper evaluation of wound depth includes use of a probe to measure wound depth and evaluate for undermining of wound edges or sinus/fistula formation. Necrotic tissue, slough, eschar: Wounds may be covered with a layer of dead tissue which may appear cream/yellow in color (slough) or as a black, hardened tissue (eschar). Removing this tissue is critical for properly evaluating both the depth of a wound and quality of the wound bed, and promotes wound healing. Wound edges: May provide clues to cause of specific wounds, such as gently sloping edges of venous ulcers or rolled edges of certain tumors.
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R2NH + R'C(O)Cl + (CH3CH2)3N → R'C(O)NR2 + [(CH3CH2)3NH]+Cl− Like other tertiary amines, it catalyzes the formation of urethane foams and epoxy resins. It is also useful in dehydrohalogenation reactions and Swern oxidations. Triethylamine is readily alkylated to give the corresponding quaternary ammonium salt:
The permissible limits for ionizing radiation intensity are consistently being revised downward. The concept of radiation protection now includes regulations for the handling of non-ionizing radiation. In the Federal Republic of Germany, radiation protection regulations are developed and issued by the Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection (BMUV). The Federal Office for Radiation Protection is involved in the technical work. In Switzerland, the Radiation Protection Division of the Federal Office of Public Health is responsible, and in Austria, the Ministry of Climate Action and Energy.
== Algorithms and software == Manual de novo sequencing is labor-intensive and time-consuming. Usually algorithms or programs come with the mass spectrometer instrument are applied for the interpretation of spectra.
Sources: en.wikipedia.org
The Ilyushin Il-86 (Russian: Илью́шин Ил-86; NATO reporting name: Camber) is a retired short- to medium-range wide-body jet airliner that served as the USSR's first wide-bodied aircraft. Designed and tested by the Ilyushin design bureau in the 1970s, it was certified by the Soviet aircraft industry, manufactured and marketed by the USSR. Developed during the rule of Leonid Brezhnev, the Il-86 was marked by the economic and technological stagnation of the era: it used engines more typical of the late 1960s, spent a decade in development, and failed to enter service in time for the 1980 Summer Olympics in Moscow, as was originally intended. The type was used by Aeroflot and successor post-Soviet airlines; only three of the total 106 constructed were exported. At the beginning of 2012, only four Il-86s remained in service, all with the Russian Air Force. By the end of 2020 the number in active service was reduced to three.
The sinuses, like other air-filled cavities, are susceptible to barotrauma if their openings become obstructed. This can result in pain as well as epistaxis (nosebleed). Diagnosis is usually simple provided the history of pressure exposure is mentioned. Barosinusitis, is also called aerosinusitis, sinus squeeze or sinus barotrauma. Sinus barotrauma can be caused by external or internal overpressure. External over-pressure is called sinus squeeze by divers, while internal over-pressure is usually referred to as reverse block or reverse squeeze.
He is also one of only two players in history to have two 40-30 seasons (Barry Bonds being the other). Bagwell is also the only first baseman to reach both 400 home runs and 200 stolen bases. He is just one of 21 players in history to win both a Rookie of the Year Award and an MVP. His 1,529 RBI during the span of his playing career ranked second for all hitters (first among right-handed hitters), and he was fifth in home runs. He was in the top 10 in the MVP voting five times. From 1994 to 2003, he led all first basemen in stolen bases, doubles, hits, runs, walks, and extra-base hits, was second in games and RBI, and was third in home runs. He is the Astros' all-time leader in home runs and RBI and is the first Astro to win an MVP. In addition to stealing over 200 bases in his career, Bagwell contributed significantly around the field as a whole. During one series against Pittsburgh in 1994, the Pirates shifted while he batted, and Bagwell responded with seven opposite-field hits. A standout defender at first base, he won the 1994 Gold Glove award. Remarked The Sporting News, "he's an extraordinary fielder who excels at charging bunts and throwing runners out at second and third. Although he has average speed, he's one of the game's smartest baserunners. ..." From 1999 to 2000, his 295 runs scored led the major leagues and set a National League two-season record.
Sources: en.wikipedia.org
It is a synthetic five-amino-acid peptide that acts as a growth hormone secretagogue. Three of its residues are non-standard amino acids, and the chain ends in an amide rather than a free acid. The molecule is small enough that it can be characterised by routine peptide analytical techniques.
It has not received marketing approval as a medicine in the United States or the European Union. Supplied material is generally described and handled as a research chemical. Regulatory treatment varies by jurisdiction, and some countries restrict growth hormone secretagogues under sports or medicines legislation.
Earlier secretagogues were associated with broader hormonal responses, including measurable changes in cortisol and prolactin. Reports on this peptide describe a narrower profile in which growth hormone release is the most prominent effect. The observation is influential because it shapes how the compound is compared with other members of the same receptor family.
The peptide is Aib-His-D-2-Nal-D-Phe-Lys-NH2. Two of its residues are non-natural, which slows enzymatic degradation. The C-terminal amide is common among bioactive peptides.