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Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Ipamorelin is a synthetic pentapeptide that belongs to the growth hormone secretagogue class of compounds. Researchers at a pharmaceutical company first described it in the 1990s while screening small peptides for growth hormone releasing activity. Its chain contains five amino acid residues, two of which are non-natural building blocks, including 2-aminoisobutyric acid and a naphthylalanine derivative. The molecule was designed to act at the ghrelin receptor while avoiding several effects observed with earlier secretagogues.
At the cellular level, ipamorelin binds the growth hormone secretagogue receptor, also called the ghrelin receptor. Activation of this receptor on pituitary somatotroph cells triggers a signaling cascade that leads to release of growth hormone into circulation. Because release follows a pulsatile pattern, studies often report peak concentration and total area under the curve rather than a single time point. Selectivity for this receptor is the property most frequently discussed in comparative work.
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 |
|---|---|---|
| Chemical class | Synthetic pentapeptide | Growth hormone secretagogue family |
| Sequence | Aib-His-D-2-Nal-D-Phe-Lys-NH2 | Contains two non-natural residues |
| Molecular formula | C38H49N9O5 | Free base form |
| Molecular weight | 711.85 g/mol | Calculated from formula |
| Primary target | GHS-R1a ghrelin receptor | Agonist activity |
Ipamorelin is a synthetic pentapeptide that acts on the growth hormone secretagogue receptor, also known as the ghrelin receptor. Its sequence contains five amino acid residues, including a non-natural residue that increases stability against enzymatic breakdown. The compound was developed in the 1990s as part of research into small peptides that stimulate pituitary hormone release. Unlike larger protein hormones, it can be produced by solid-phase peptide synthesis and characterized by standard analytical methods.
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.
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。
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。
=== The name === The word Pseudomonas means false unit, being derived from the Greek words pseudēs (Greek: ψευδής – false) and monas (Latin: monas, from Greek: μονάς – a single unit). The word was used early in the history of microbiology to refer to germs. The specific name fluorescens refers to the microbe's secretion of a soluble fluorescent pigment called pyoverdin, which is a type of siderophore.
== Selected publications == Moloney, P. J. (1926). "The preparation and testing of diphtheria toxoid (Anatoxine-Ramon)". American Journal of Public Health. 16 (12): 1208–1210. doi:10.2105/AJPH.16.12.1208. PMC 1321494. PMID 18012024. Moloney, P. J.; Fraser, C. J. (1927). "Immunization with diphtheria toxoid (anatoxine Ramon)". American Journal of Public Health. 17 (10): 1027–1030. doi:10.2105/AJPH.17.10.1027. PMC 1321911. PMID 18012293. Taylor, E. M.; Moloney, P. J. (1939). "A New Schick-Toxin". The Journal of Immunology. 37 (3): 223–232. doi:10.4049/jimmunol.37.3.223. S2CID 86572393. Fitzgerald, J. G.; Defries, R. D.; Fraser, D. T.; Moloney, P. J.; McKinnon, N. E. (1932). "Experiences with Diphtheria Toxoid in Canada". American Journal of Public Health and the Nation's Health. 22 (1): 25–28. doi:10.2105/ajph.22.1.25. PMC 1556712. PMID 18013424. Moloney, P. J.; Hennessy, J. N. (1942). "Purification of tetanus toxoid". The Biochemical Journal. 36 (7–9): 544–547. doi:10.1042/bj0360544. PMC 1266838. PMID 16747558. Moloney, P. J.; Hennessy, Joan N. (1944). "Titration of Tetanal Toxins and Toxoids by Flocculation". The Journal of Immunology. 48 (6): 345–354. doi:10.4049/jimmunol.48.6.345. S2CID 88201977. Moloney, P. J.; Coval, M. (1955). "Antigenicity of insulin: Diabetes induced by specific antibodies". The Biochemical Journal. 59 (2): 179–185. doi:10.1042/bj0590179. PMC 1216116. PMID 14351177. Moloney, P. J.; Goldsmith, L. (1957). "On the Antigenicity of Insulin". Canadian Journal of Biochemistry and Physiology. 35 (1): 79–92. doi:10.1139/y57-011. PMID 13396665.
==== Cell cycle regulation ==== Cyclins are a group of proteins that activate kinases involved in cell division. The degradation of cyclins is the key step that governs the exit from mitosis and progress into the next cell cycle. Cyclins accumulate in the course the cell cycle, then abruptly disappear just before the anaphase of mitosis. The cyclins are removed via a ubiquitin-mediated proteolytic pathway.
9-Carboxymethoxymethylguanine (CMMG) is a compound which is known as the principal metabolite of the antiviral medication aciclovir (and its prodrug valaciclovir), and has been suggested as the causative agent in the neuropsychiatric side effects sometimes associated with these medications. These are mainly suffered by patients with kidney failure or otherwise decreased kidney function, and can include psychotic reactions, hallucinations, and rarely more complex disorders such as Cotard delusion. Patients suffering these symptoms following aciclovir treatment were found to have much higher levels of CMMG than normal, and since this is the first time Cotard delusion has been linked to a drug as a side effect, this discovery may be useful in the study of Cotard delusion and its treatment.
Sources: en.wikipedia.org
==== Protease-specific Arrays ==== A protease specific protein array based on immobilized antibodies designed to capture specific proteases from biological samples offers a step up in analysis of protein levels beyond transcript expression. Capture antibodies spotted to nitrocellulose membranes can bind proteases in complex mixtures which have been pre-incubated and bound by detection antibodies allowing for parallel analysis of relative protease levels. These arrays offer parallelization of protein levels over traditional western blot. Unfortunately, these assays fail to provide insight on enzymatic function for proteases and suffer similar drawbacks to western blots regarding reliable quantification.
A pariah field, cast out by the scientific establishment. Between cold fusion and respectable science there is virtually no communication at all. Cold fusion papers are almost never published in refereed scientific journals, with the result that those works don't receive the normal critical scrutiny that science requires. On the other hand, because the Cold-Fusioners see themselves as a community under siege, there is little internal criticism. Experiments and theories tend to be accepted at face value, for fear of providing even more fuel for external critics, if anyone outside the group was bothering to listen. In these circumstances, crackpots flourish, making matters worse for those who believe that there is serious science going on here.
The Australian Defence Force currently supplies three different types of military ration packs – Combat Ration One Man, Combat Ration Five Man and Patrol Ration One Man. Combat Ration One Man is a complete 24-hour ration pack that provides two substantial meals per day and a wide variety of drinks and snacks for the remainder of the day. Most items, such as Beef Kai Si Ming, Dutch-style Beef with Vegetables, Beef with Spaghetti, Baked Beans, Sausages with Vegetables, or Chicken with pasta and vegetables, are packed in 250 gram sized plastic-foil retort pouches. Included with every meal pack is a pouch of instant rice or instant mashed potatoes, a fruit and grain bar, 2 envelopes of instant drink powder, some biscuits, an "Anzac Biscuit", a chocolate bar, M&M's, coffee, tea, sugar, crackers, cheese spread, jam, sweetened condensed milk, hard sweets, and Vegemite. It is packed in a tough clear polyethylene bag and weighs around 1.5–1.7 kg (3.3–3.7 lb). In practical use, these packs are "stripped" by removing and trading with other soldiers, those components that are unlikely to be consumed by the person carrying the pack. This also reduces the weight of the packs, allowing more to be carried. There are eight menu choices, one of which is vegetarian. None of them are allergen free since Defence Force members are typically selected, among many other attributes, for their no known allergy status. Combat Ration Five Man contains a similar array of components as the Combat Ration One Man.
Sources: en.wikipedia.org
It is a synthetic pentapeptide in the growth hormone secretagogue family. The chain contains five residues, two of which are non-natural amino acids.
It acts as an agonist at the growth hormone secretagogue receptor, also known as the ghrelin receptor. Binding at pituitary somatotroph cells promotes growth hormone release.
Early studies report weaker effects on cortisol, prolactin, and appetite than compounds such as GHRP-6. The size of that difference in humans is not firmly established.
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.