This is a working overview of GHS-R1a, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-04-10. Anything still debated is marked as such rather than presented as settled.
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 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.
| 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 |
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.
The lyophilised solid is normally held at -20 °C or colder, shielded from light and moisture. Stability in that state is measured in years, although shelf life depends on residual water content and the container seal. Once dissolved, the peptide is more fragile: aqueous solutions are commonly kept at 2-8 °C and used within days to weeks, and repeated freeze-thaw cycling is avoided. Strongly acidic or basic conditions accelerate hydrolysis, and prolonged exposure to them can strip the terminal amide.
Purity assessment for this peptide relies mainly on reversed-phase high-performance liquid chromatography. A C18 column with a water-acetonitrile gradient containing trifluoroacetic acid separates the target from truncated sequences and oxidation products. Detection near 214 nm exploits the amide backbone, while the aromatic side chains allow additional monitoring close to 280 nm. Reported purity values depend on the method, so a certificate of analysis carries weight only when gradient, column and integration parameters are given.
A potential risk of frequent repeated long-term use of LSD and other serotonergic psychedelics is cardiac fibrosis and valvulopathy due to serotonin 5-HT2B receptor agonism. This may also be the case with microdosing. However, the risks are theoretical, and more research is needed to see if these complications can actually occur with psychedelics. A preliminary animal study found that chronic microdosing of LSD did not result in heart structure changes or valvulopathy in rodents. Research appears to be mixed on whether LSD is a potent serotonin 5-HT2B receptor agonist or not, with some studies finding it to be essentially inactive.
The Census Bureau's 2006–2010 American Community Survey showed that (in 2010 inflation-adjusted dollars) median household income was $105,625 (with a margin of error of +/− $14,945) and the median family income was $128,382 (+/− $16,732). Males had a median income of $95,795 (+/− $24,665) versus $72,188 (+/− $16,155) for females. The per capita income for the borough was $56,485 (+/− $6,202). About 2.4% of families and 4.0% of the population were below the poverty line, including 1.8% of those under age 18 and 9.4% of those age 65 or over.
Monotremes have some features which may be inherited from the original amniotes such as the same orifice to urinate, defecate and reproduce (cloaca)—as reptiles and birds also do— and they lay eggs which are leathery and uncalcified.
After the corporate acquisition of the original patent holder, the pharmaceutical company Pfizer admitted that there had been violations of FDA guidelines regarding the promotion of unproven off-label uses for gabapentin in the Franklin v. Parke-Davis case. While off-label prescriptions are common for many drugs, marketing of off-label uses of a drug is not. In 2004, Warner-Lambert (which subsequently was acquired by Pfizer) agreed to plead guilty for activities of its Parke-Davis subsidiary, and to pay $430 million in fines to settle civil and criminal charges regarding the marketing of Neurontin for off-label purposes. The 2004 settlement was one of the largest in US history up to that point, and the first off-label promotion case brought successfully under the False Claims Act. Kaiser Foundation Hospitals and Kaiser Foundation Health Plan sued Pfizer Inc., alleging that the pharmaceutical company had misled Kaiser by recommending Neurontin as an off-label treatment for certain conditions (including bipolar disorder, migraines, and neuropathic pain). In 2010, a federal jury in Massachusetts ruled in Kaiser's favor, finding that Pfizer violated the federal Racketeer Influenced and Corrupt Organizations (RICO) Act and was liable for US$47.36 million in damages, which was automatically trebled to just under $142.1 million. Aetna, Inc. and a group of employer health plans prevailed in their similar Neurontin-related claims against Pfizer.
Sources: en.wikipedia.org
TikTok's and Douyin's censorship policies have been criticized as non-transparent. Internal guidelines against the promotion of violence, separatism, and "demonization of countries" could be used to prohibit content related to the 1989 Tiananmen Square protests and massacre, Falun Gong, the Cambodian genocide, the 1998 Indonesian riots, Kurdish nationalism, ethnic conflicts between blacks and whites or between different Islamic sects, and independence movements in Tibet, Taiwan, Chechnya and Northern Ireland. A more specific list banned criticisms against world leaders, including past and present ones from Russia, the United States, Japan, North and South Korea, India, Indonesia, and Turkey. In 2019, The Guardian reported that TikTok had censored videos of topics not favored by the Chinese government. That year, TikTok took down a video about human rights abuses in the Xinjiang internment camps against Uyghurs but restored it after 50 minutes as well as the creator's account, saying that the action was a mistake and triggered by a brief "satirical" image of Osama bin Laden in another post. Other human rights activists have also said that their TikTok videos discussing human rights violations of the Uyghurs have been taken down. TikTok moderators were instructed to suppress posts from "For You" recommendations if the users shown were deemed "too ugly, poor, or disabled". The consumption of alcohol, full or partial nudity, LGBT, and intersex contents were restricted even in places where they are legal.
火 (huǒ, fire) e.g.: 烷 (wán, alkane), common for hydrocarbons 酉 (yǒu, ritual wine vessel) e.g.: 酮 (tóng, ketone), common for oxygenated functionalities 艸 (cǎo, grass) e.g. 苯 (běn, benzene, phenyl), common for aromatic compounds and terpenes 肉 (ròu, meat, flesh) e.g. 腙 (zōng, hydrazone), common for nitrogen-containing functionalities Additionally, the mouth radical (口, kǒu) is affixed to characters that are used for their sound only. This occurs often in the transliteration of the names of heterocyclic compounds, (e.g., 吡啶, "bǐdìng", pyridine). These characters are also used for the transliteration of non-chemical terms from foreign languages.
Engineers for the Metropolitan Vickers Electrical Company were given a show trial and deported in 1933, ending the role of British business in the USSR. Today, the Moscow Metro comprises 12 lines, mostly underground, with a total of 203 stations. It is one of the deepest subway systems in the world; for instance, the Park Pobedy station, completed in 2003, 84 meters (276 ft) underground, has the longest escalators in Europe. The Moscow Metro is the busiest such system in Europe, as well as one of the world's busiest, serving about ten million passengers daily (300 million people each month). As of 2016, facing serious transportation problems, Moscow planned to expand its metro. That year, the authorities launched a new circle metro railway that helped to solve transportation problems, namely daily congestion on the Koltsevaya line. Because metro stations were treated as potential media for art—because workers in Moscow could see such art every day—many Stalin-era metro stations were built using customized designs; each station's design was initially a large installation on a specific theme. For example, the Elektrozavodskaya station was themed on a nearby lightbulb factory and ceramic ribbed lightbulb sockets. The tradition of "Grand Designs"—essentially decorating a metro station as a single-themed installation—was restored in late 1979. Moscow's metro is one of the world's busiest, handling 2.6 billion passengers in 2019.
An analysis of GPX1 expression in oligodendrocytes from patients with major depressive disorder and control patients showed that GPX1 levels were significantly decreased in patients with the disorder, but not in their astrocytes. Shortening of telomeres and decreased expression of telomerase were also evident in these oligodendrocytes, but not in the astrocytes in these patients. This suggests that decreased oxidative stress protection, as observed by decreased GPX1 levels, and decreased telomerase expression may help give rise to telomere shortening in patients with MDD.
Moxidectin has a longer half-life than ivermectin and may eventually supplant ivermectin as it is a more potent microfilaricide, but there is a need for additional clinical trials, with long-term follow-up, to assess whether moxidectin is safe and effective for treatment of nematode infection in children and women of childbearing potential. There is tentative evidence that ivermectin kills bedbugs, as part of integrated pest management for bedbug infestations. However, such use may require a prolonged course of treatment which is of unclear safety.
Sources: en.wikipedia.org
== Plot == Rick Rambis, best friend Luke, and other friends Anthony, "Pig Pen", Jenny, Lance and Stumpy, all live and work at a ski resort on Bull Mountain in Alaska. The mountain and resort were founded by Herbert "Papa" Muntz who stole the land from the Eskimos and loved to drink and ski at the same time until he died doing so. His son, Ted, took over the mountain and plans to sell it to wealthy Colorado ski resort tycoon John Majors. In addition to being friends, Rick has romantic designs on Jenny, but is held back as he is still getting over his ex, Anna, who mysteriously disappeared after 3 weeks of summer love in Mexico. After arriving at the mountain, John Majors plans to change the mountain name and turn the ski village into a first class resort but seeks Rick's help in getting his rowdy friends in line so as not to scare off his investors. John brings with him to the mountain his daughters, Inga, a Swiss ski bunny, and Anna, Rick's summer fling. After Anna's arrival, Rick then gets drunk and misses his date with Jenny. Later, Anna explains she left Rick in Mexico because she was already engaged to a doctor named Barry, who suffered an injury during the X Games, now a wheelchair user, and that Rick was the other man. Majors begins to make major changes to the town and mountain, such as changing the dive bar to an upscale club called Powder Room, removing the statue of Papa Muntz from the center of the town, and evicting some folks from their homes. Majors offers Rick a contract to be his new manager and Rick agrees on the condition that his friends all get to stay.
Germany's system of hospitals, called Krankenhäuser, dates from medieval times, and the country has the world's oldest universal health care system, dating from Bismarck's social legislation of the 1880s. Since the 1880s, reforms and provisions have ensured a balanced health care system. The population is covered by a health insurance plan provided by statute, with criteria allowing some groups to opt for a private health insurance contract. According to the World Health Organization (WHO), Germany's health care system was 77% government-funded and 23% privately funded in 2013. In 2024, Germany spent 12.27% of its GDP on health care. Germany ranked 21st in the world in 2019 in life expectancy with 78.7 years for men and 84.8 years for women according to the WHO, and it had a very low infant mortality rate of 4 deaths per 1,000 live births. In 2019, the principal cause of death was cardiovascular disease, at 37%. Obesity in Germany has been increasingly cited as a major health issue: a 2014 study showed that 52 percent of the adult German population was overweight or obese. Germany has an extensive psychiatric care system, with rising demand for mental health services; roughly 27.8% of adults experience a mental disorder annually. While the system offers comprehensive, insurance-covered care, it faces a shortage of psychotherapists and a pandemic-driven surge in anxiety and depression. In 2023, 37.7% of adults rated their mental health as excellent or very good. Germany had the third-highest rate of chronic depression among EU countries in 2019.
== Available forms == Both the oral and intravenous preparations of flucloxacillin are inexpensive and are available as the sodium salt flucloxacillin sodium, in capsules (250 or 500 mg), oral suspensions (125 mg/5 ml or 250 mg/5 ml), and injections (powder for reconstitution, 250, 500, 1000 and 2000 mg per vial). Flucloxacillin is not commonly used in the United States or Canada as of 2011, but is the most commonly prescribed narrow-spectrum penicillinase-resistant penicillin in the UK. It is supplied under a variety of trade names including Floxapen, Flopen, Flubex, Flupen, Phylopen, and Staphylex.
The center of the DNA junction constitutes a volume on the order of a yoctoliter, hence the name YoctoReactor. This volume contains a single molecule reaction yielding reaction concentrations in the high mM range. The effective concentration facilitated by the DNA greatly accelerates chemical reactions that otherwise would not take place at the actual concentration several orders of magnitude lower.
White nose syndrome is a condition associated with the deaths of millions of bats in North America. The disease is named after a white fungus, Pseudogymnoascus destructans, found growing on the muzzles, ears, and wings of affected bats. The fungus is mostly spread from bat to bat and causes weight loss, dehydration and electrolyte imbalances. The fungus was first discovered in central New York State in 2006 and spread to 30 US states and five Canadian provinces; mortality rates as high as 99% have occurred for affected bat wintering caves. To treat the disease, scientists have used probiotic dermal bacteria and antifungal vaccines, which can improve survival by as much as 50%. Bats are natural reservoirs for a large number of zoonotic pathogens, including rabies, endemic in many bat populations; histoplasmosis, both directly and in guano; Nipah and Hendra viruses; and possibly the Ebola virus. Their high mobility, broad distribution, long life spans, substantial sympatry (range overlap) of species, and social behaviour make bats favourable hosts and vectors of disease. Reviews have found different answers as to whether bats have more zoonotic viruses (transferable to humans) than other mammal groups. One 2015 review found that among mammals, bats, rodents, and primates harboured the most zoonotic viruses by a significant margin, though bats had about as many zoonotic viruses as rodents and primates. Another 2020 review of mammals and birds found that the taxon of the reservoir was not a factor in whether a virus was zoonotic.
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。
Ipamorelin is a synthetic pentapeptide that stimulates growth hormone release by activating the ghrelin receptor. It is handled as a research tool rather than as a licensed therapeutic product. Its short chain length makes it comparatively simple to synthesize and analyze.