secretagogue 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 2025-08-30 and is reviewed periodically as new material appears.
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。
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。
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.
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.
| Property | Value | Notes |
|---|---|---|
| 分子式 | C38H49N9O5 | 五肽，含非天然氨基酸残基 |
| 分子量 | 711.85 g/mol | 理论值，盐形式可能略有差异 |
| 外观 | 白色至类白色粉末 | 冻干粉常见 |
| 溶解性 | 易溶于水 | 也可溶于部分极性有机溶剂 |
| 储存条件 | -20°C，干燥避光 | 长期保存通常推荐 |
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.
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.
Compared with older secretagogues such as hexarelin or GHRP-6, ipamorelin shows weaker stimulation of cortisol, prolactin, and appetite in the animal models used for early characterization. Whether that selectivity is preserved across longer human exposures remains an open question, because published clinical data are limited in size and duration. Reported effects on food intake are generally described as modest. The compound is therefore treated in the literature as a relatively selective research tool rather than a fully characterized therapeutic agent.
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.
In animal and early human studies, ipamorelin produces pulsatile growth hormone release and a secondary rise in insulin-like growth factor 1. The magnitude and duration of that rise depend on route, sampling schedule, and the baseline endocrine state of the subject. Whether repeated exposure alters the response over time is not firmly settled, since some reports describe stable pulsatility while others note attenuation. Most published data come from small samples, which limits the strength of any general claim about long-term behavior.
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.
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.
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.
In November 2021, CleanTechnica reported that Tesla would be opening Superchargers at 26 Buc-ee's locations in seven states. As of February 2023, there were operational Superchargers at more than half of the planned locations including in Alabama (Leeds and Robertsdale); Florida (St. Augustine); South Carolina (Florence); Tennessee (Crossville); and Texas (Bastrop, Baytown, Ennis, Giddings, Katy, Madisonville, Melissa, New Braunfels, and Wharton). Since then, more Superchargers have been added into more locations, such as in Colorado (Berthoud); Florida (Daytona Beach); Georgia (Adalrsville and Fort Valley); Kentucky (Richmond); Tennessee (Kodak); and Texas (Denton, Fort Worth, Luling, Pearland, Royse City, Temple, Terrell, and Waller).
enterica-induced intestinal inflammation, which indicates that PGLYRP2 also has anti-inflammatory effect in the intestinal tract. However, PGLYRP2 also has opposite effects. PGLYRP2-deficient mice are more resistant than wild type mice to the development of arthritis induced by systemic administration of peptidoglycan or MurNAc-L-Ala-D-isoGln peptidoglycan fragment (muramyl dipeptide, MDP). In this model, PGLYRP2 is required for the production of chemokines and cytokines that attract neutrophils to the arthritic joints. PGLYRP2-deficient mice are also more resistant than wild type mice to bacterially induced keratitis and inflammation in S. pneumoniae-induced lung infection. Moreover, PGLYRP2-deficient mice are more resistant to weight loss in a model of chemotherapy-induced gastrointestinal toxicity, which indicates that in wild type mice PGLYRP2 contributes to the chemotherapy-induced weight loss. PGLYRP2 also promotes NOD2-induced production of proinflammatory cytokines in macrophages. These results indicate that under certain conditions PGLYRP2 has pro-inflammatory effects. PGLYRP2-deficient mice also show higher sociability and decreased levels of anxiety-like behaviors compared with wild type mice, which indicate that PGLYRP2 affects behavior in mice.
effective molecular diameter The physical extent of the electron cloud surrounding a molecule of a particular gas, as calculated in any of several ways and usually expressed in nanometres or ångströms.
== Development of first generation ACE inhibitors == The development of the nonapeptide teprotide (Glu-Trp-Pro-Arg-Pro-Gln-Ile-Pro-Pro), which was originally isolated from the venom of the Brazilian pit viper Bothrops jararaca, greatly clarified the importance of ACE in hypertension. However, its lack of oral activity limited its therapeutic utility. L-benzylsuccinic acid (2(R)-benzyl-3-carboxypropionic acid) was described to be the most potent inhibitor of carboxypeptidase A in the early 1980s. The authors referred to it as a by-product analog and it was proposed to bind to the active site of carboxypeptidase A via succinyl carboxyl group and a carbonyl group. Their findings established that L-benzylsuccinic acid is bound at a single locus at the active site of carboxypeptidase A. The authors discussed but dismissed the suggestion that the carboxylate function might bind to the catalytically functional zinc ion present at the active site. Later however this was found to be the case.
Sources: en.wikipedia.org
== Neoantigenic determinant == A neoantigenic determinant is an epitope on a neoantigen, which is a newly formed antigen that has not been previously recognized by the immune system. Neoantigens are often associated with tumor antigens and are found in oncogenic cells. Neoantigens and, by extension, neoantigenic determinants can be formed when a protein undergoes further modification within a biochemical pathway such as glycosylation, phosphorylation or proteolysis. This, by altering the structure of the protein, can produce new epitopes that are called neoantigenic determinants as they give rise to new antigenic determinants. Recognition requires separate, specific antibodies.
=== Consumer product development === Many other industries take into account distribution coefficients, for example in the formulation of make-up, topical ointments, dyes, hair colors and many other consumer products.
An ion-exchange resin such as chelex 100, which contains chelating ligands bound to a polymer, can be used in water softeners and in chromatographic separation techniques. In solvent extraction the formation of electrically neutral complexes allows cations to be extracted into organic solvents. For example, in nuclear fuel reprocessing uranium(VI) and plutonium(VI) are extracted into kerosene as the complexes [MO2(TBP)2(NO3)2] (TBP = tri-n-butyl phosphate). In phase-transfer catalysis, a substance which is insoluble in an organic solvent can be made soluble by addition of a suitable ligand. For example, potassium permanganate oxidations can be achieved by adding a catalytic quantity of a crown ether and a small amount of organic solvent to the aqueous reaction mixture, so that the oxidation reaction occurs in the organic phase. In all these examples, the ligand is chosen on the basis of the stability constants of the complexes formed. For example, TBP is used in nuclear fuel reprocessing because (among other reasons) it forms a complex strong enough for solvent extraction to take place, but weak enough that the complex can be destroyed by nitric acid to recover the uranyl cation as nitrato complexes, such as [UO2(NO3)4]2− back in the aqueous phase.
== Personal life == Woolley married bacteriologist Janet Ruth McCarter in 1945. Woolley had Diabetes mellitus type 1 from childhood, and in 1923 was among the first children to receive insulin to treat the condition. He nonetheless experienced blindness as a complication of his diabetes, and was completely blind from age 25 until his death from a heart attack at age 52, while hiking in Cuzco, Peru.
=== Pharmacodynamics === Gabapentinoids are high affinity ligands of the α2δ protein that was first described as an auxiliary subunit of certain voltage-gated calcium channels (VGCC). All of the known pharmacological actions of gabapentinoids require binding at this site. There are two drug-binding α2δ subunits, α2δ-1 and α2δ-2, and most gabapentinoids show similar affinity for (and hence lack of selectivity between) these two sites. In most cases, gabapentinoid drugs do not seem to directly alter the action of VGCC and instead reduce the release of certain excitatory neurotransmitters. (However, see). The gabapentinoid drugs do not bind significantly to other known drug receptors and so the α2δ VGCC subunit has been called the gabapentin receptor. Recently, the same α2δ-1 protein has been found closely associated not with VGCCs but with other proteins such as presynaptic NMDA-type glutamate receptors, cell adhesion molecules such as thrombospondin and others. Gabapentinoids alter the function of these additional α2δ binding proteins, and these have been proposed as mediators of drug actions. Despite the fact that gabapentinoids are GABA analogues, gabapentin and pregabalin do not bind to GABA receptors, do not convert into GABATooltip γ-aminobutyric acid or GABA receptor agonists in vivo, and do not modulate GABA transport or metabolism. Conversely, GABA does not bind appreciably to the α2δ protein. Furthermore, gabapentinoids do not act directly as inhibitors or blockers of VGCC.
Sources: en.wikipedia.org
Brazilian law is based on the civil law legal system and civil law concepts prevail over common law practice. Most of Brazilian law is codified, although non-codified statutes also represent a substantial part, playing a complementary role. While court decisions historically served primarily as interpretive guidelines, modern legal reforms have established binding judicial precedents across higher courts to ensure legal predictability. Doctrinal works and the works of academic jurists have a strong influence on law creation and in law cases. Judges and other judicial officials are appointed after passing entry exams. The legal system is based on the Federal Constitution, promulgated on 5 October 1988, and the fundamental law of Brazil. All other legislation and court decisions must conform to its rules. As of July 2022, there have been 124 amendments. The highest court is the Supreme Federal Court. States have their own constitutions, which must not contradict the Federal Constitution. Municipalities and the Federal District have "organic laws" (leis orgânicas), which act in a similar way to constitutions. Legislative entities are the main source of statutes, although in certain matters judiciary and executive bodies may enact legal norms. Jurisdiction is administered by the judiciary entities, although in rare situations the Federal Constitution allows the Federal Senate to pass on legal judgments. There are also specialized military, labor and electoral courts.
Researchers provided a depression questionnaire to 487 overweight/obese subjects and found that 7% of those with low depression symptoms were using antidepressants and had an average BMI score of 44.3, 27% of those with moderate depression symptoms were using antidepressants and had an average BMI score of 44.7, and 31% of those with major depression symptoms were using antidepressants and had an average BMI score of 44.2. Several studies have also explored the connection between Attention-deficit hyperactivity disorder (ADHD) and obesity in children. A study in 2005 concluded that within a subgroup of children who were hospitalized for obesity, 57.7% had co-morbid ADHD. This relationship between obesity and ADHD may seem counter-intuitive, as ADHD is typically associated with higher level of energy expenditure, which is thought of as a protective factor against obesity. However, these studies determined that children exhibited more signs of predominantly inattentive-type ADHD rather than combined-type ADHD. It is possible, however, that the symptoms of hyperactivity typically present in individuals with combined-type ADHD are simply masked in obese children with ADHD due to their decreased mobility. The same correlation between obesity and ADHD is also present in adult populations.
If oxygen saturation in sea water drops to about 1–10% it can be fatal for Octopus vulgaris depending on the weight of the animal and the water temperature. Ventilation may increase to pump more water carrying oxygen across the gills but due to receptors found on the gills the energy use and oxygen uptake remains at a stable rate. The high percent of oxygen extraction allows for energy saving and benefits for living in an area of low oxygen concentration. Water is pumped into the mantle cavity of the octopus, where it comes into contact with the internal gills. The water has a high concentration of oxygen compared to the blood returning from the veins, so oxygen diffuses into the blood. The tissues and muscles of the octopus use oxygen and release carbon dioxide when breaking down glucose in the Krebs cycle. The carbon dioxide then dissolves into the blood or combines with water to form carbonic acid, which decreases blood pH. The Bohr effect explains why oxygen concentrations are lower in venous blood than arterial blood and why oxygen diffuses into the bloodstream. The rate of diffusion is affected by the distance the oxygen has to travel from the water to the bloodstream as indicated by Fick's laws of diffusion. Fick's laws explain why the gills of the octopus contain many small folds that are highly vascularized. They increase surface area, thus also increase the rate of diffusion. The capillaries that line the folds of the gill epithelium have a very thin tissue barrier (10 μm), which allows for fast, easy diffusion of the oxygen into the blood.
In February 2013, proteogenomic mapping research was done with ENCODE to identify translational regions in the human genome. They applied peptide fingerprint scanning and MASCOT to the protein data to find regions that may not have been previously annotated as translated in the human genome. This search against the whole genome revealed that approximately 4% of unique peptide that they found were outside of previously annotated regions. Also the comparison of the whole genome revealed 15% more hits than from a protein database search (such as MASCOT) alone. GFS can be used as a complementary method for annotation due to the fact that you can find new genes or splice sites that have not been annotated before. However it is important to remember that the whole genome approach used by GFS can be less sensitive than programs that look only at annotated regions.
Plastic surgery can be performed to augment or reduce the size of breasts, or to reconstruct the breast in cases of deformative disease, such as breast cancer. Breast augmentation and breast lift (mastopexy) procedures are done only for cosmetic reasons, whereas breast reduction is sometimes medically indicated. In cases where a woman's breasts are severely asymmetrical, surgery can be performed to either enlarge the smaller breast, reduce the size of the larger breast, or both. Breast augmentation surgery generally does not interfere with future ability to breastfeed. Breast reduction surgery more frequently leads to decreased sensation in the nipple-areola complex, and to low milk supply in women who choose to breastfeed. Implants can interfere with mammography (breast x-ray images).
Sources: en.wikipedia.org
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。
生长激素释放激素通过其专用受体起作用，而 ipamorelin 主要作用于胃饥饿素受体。两者可影响生长激素释放，但信号通路和下游效应并不相同。
研究多集中在生长激素释放的急性调节、受体选择性以及不同给药方式下的药代动力学。临床终点研究数量有限，长期结局尚不明确。
It acts on the growth hormone secretagogue receptor, GHS-R1a, which is also the receptor for ghrelin. Binding triggers intracellular signaling that promotes growth hormone release from the pituitary. The interaction is the basis for its classification as a secretagogue.