The short version of secretagogue fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-05-16. Anything still debated is marked as such rather than presented as 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.
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.
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.
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.
| 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 |
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.
Lyophilized material is generally held at minus twenty degrees Celsius or lower, protected from moisture and light. Repeated excursions to room temperature cause condensation inside the vial and gradual moisture uptake, both of which shorten shelf life. Containers should be allowed to equilibrate before opening so that water does not condense on the solid. Dividing a batch into single-use aliquots reduces freeze-thaw cycling. Solid peptide handled this way is usually considered stable for months to years, while the same material in solution degrades on a much shorter timescale.
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.
They described MDMA as inducing "an easily controlled altered state of consciousness with emotional and sensual overtones" comparable "to marijuana, to psilocybin devoid of the hallucinatory component, or to low levels of MDA". While not finding his own experiences with MDMA particularly powerful, Shulgin was impressed with the drug's disinhibiting effects and thought it could be useful in therapy. Believing MDMA allowed users to strip away habits and perceive the world clearly, Shulgin called the drug window. Shulgin occasionally used MDMA for relaxation, referring to it as "my low-calorie martini", and gave the drug to friends, researchers, and others who he thought could benefit from it. One such person was Leo Zeff, a psychotherapist who had been known to use psychedelic substances in his practice. When he tried the drug in 1977, Zeff was impressed with the effects of MDMA and came out of his semi-retirement to promote its use in therapy. Over the following years, Zeff traveled around the United States and occasionally to Europe, eventually training an estimated four thousand psychotherapists in the therapeutic use of MDMA. Zeff named the drug Adam, believing it put users in a state of primordial innocence. Psychotherapists who used MDMA believed the drug eliminated the typical fear response and increased communication. Sessions were usually held in the home of the patient or the therapist. The role of the therapist was minimized in favor of patient self-discovery accompanied by MDMA induced feelings of empathy.
=== Gott ist schön (dissertation 1998) === In his dissertation Gott ist schön (God is Beautiful), which focuses on reception aesthetics and philology, Kermani shows how prominently Islamic tradition perceives the aesthetic dimension of the Koran. The Koran is described as a beguiling, captivating work of art, its beauty capturing people's hearts with an irresistible appeal. The beauty and clarity of the Koran is thus proof of its divine inspiration. According to this conception, God communicates in the Koran in an aesthetically mediated way in hopes to be understood accordingly by those whom the Koran addresses. If God seeks understanding recognition rather than blind obedience, he must encounter receptive people in an aesthetic way. For—at least according to Navid Kermani's thesis informed by his analytical view of Islamic tradition—religious recognition in Islam is conveyed aesthetically as the thrilling, goose bump-inducing hearing of a language described as beautiful, i.e. as an experience of beauty. Kermani is therefore concerned with appreciating the power of aesthetics on a religious level. He views this mystical insight as being entirely in line with the more recent Western aesthetics since Hegel. In almost all philosophical theories of art in the modern tradition, aesthetic experience is about truth. Indeed, contrary to Kant, aesthetic experience need not be about enjoyment or disinterested pleasure. It may simply be about discovering the truth, whatever the cost.
==== Increased throughput ==== While DMF systems cannot match the same throughput achieved by some liquid handling pipetting robots, or by some droplet-based microfluidic systems, there are still throughput advantages when compared to conventional methods carried out manually.
Sources: en.wikipedia.org
== Specific varieties == Tripolite is the variety found in Tripoli, Libya. Bann clay is the variety found in the Lower Bann valley in Northern Ireland. Moler (mo-clay) is the variety found in northwestern Denmark, especially on the islands of Fur and Mors. Freshwater-derived food grade diatomaceous earth is the type used in United States agriculture for grain storage, as feed supplement, and as an insecticide. It is produced uncalcinated, has a very fine particle size, and is very low in crystal silica (<2%). Salt-water-derived pool / beer / wine filter grade is not suitable for human consumption or effective as an insecticide. Usually calcinated before being sold to remove impurities and undesirable volatile contents, it is composed of larger particles than the freshwater version and has a high crystalline silica content (>60%).
PKB also phosphorylates glycogen synthase kinase (GSK), thereby inactivating this enzyme. This means that its substrate, glycogen synthase (GS), cannot be phosphorylated, and remains dephosphorylated, and therefore active. The active enzyme, glycogen synthase (GS), catalyzes the rate limiting step in the synthesis of glycogen from glucose. Similar dephosphorylations affect the enzymes controlling the rate of glycolysis leading to the synthesis of fats via malonyl-CoA in the tissues that can generate triglycerides, and also the enzymes that control the rate of gluconeogenesis in the liver. The overall effect of these final enzyme dephosphorylations is that, in the tissues that can carry out these reactions, glycogen and fat synthesis from glucose are stimulated, and glucose production by the liver through glycogenolysis and gluconeogenesis are inhibited. The breakdown of triglycerides by adipose tissue into free fatty acids and glycerol is also inhibited. After the intracellular signal that resulted from the binding of insulin to its receptor has been produced, termination of signaling is then needed. As mentioned below in the section on degradation, endocytosis and degradation of the receptor bound to insulin is a main mechanism to end signaling. In addition, the signaling pathway is also terminated by dephosphorylation of the tyrosine residues in the various signaling pathways by tyrosine phosphatases. Serine/Threonine kinases are also known to reduce the activity of insulin.
=== Names === Diamorphine is the international nonproprietary name and the British Approved Name. Other synonyms for heroin include: diacetylmorphine, and morphine diacetate. Heroin is also known by many street names including Big H, Black Tar, Chiva, Hell Dust, Horse, Negra, Smack, Thunder, dope, H, smack, junk, skag, brown, and unga among others. Whoonga (or wonga), nyaope and sugars are South African street names for heroin.
== External links == "Atomic weights and isotopic compositions". physics.nist.gov. Physical Reference Data. National Institute for Standards and Technology. 23 August 2009. "Atomic mass unit". sizes.com. Archived from the original on 2008-01-15.
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.
Dry powder is typically kept frozen, desiccated, and protected from light. Avoiding moisture exposure and large temperature swings helps slow degradation. Storage recommendations vary by supplier and should be followed for the specific material.