This is a working overview of secretagogue, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-12-22 and is reviewed periodically as new material appears.
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.
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.
| 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 |
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.
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.
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。
Research quantities of ipamorelin are typically distributed as a white to off-white lyophilized powder. The solid dissolves readily in water and in aqueous buffers, and stock solutions are commonly prepared in sterile water or a mildly acidic diluent. Adsorption to plastic and glass surfaces can reduce the concentration of very dilute solutions, so containers and transfer steps deserve attention when accurate concentrations matter. Reconstituted material is generally used promptly rather than held for extended periods.
Storage recommendations for the dry solid center on low temperature and low moisture, most often -20 °C in a sealed, desiccated container protected from light. Solutions are less stable than the powder and are usually kept cold and used within a short window. Freeze-thaw cycling is a recognized source of loss, and aliquoting before freezing is a standard precaution. These practices derive from general peptide handling principles rather than from a single published stability trial, so exact shelf lives should be treated as approximate.
Long-term storage of the dry powder is typically at minus twenty degrees Celsius or lower, protected from light and moisture. Solutions are commonly kept frozen and thawed only once, because repeated freeze-thaw cycles can promote aggregation and loss of measurable peptide content. Buffers near neutral pH are preferred over strongly acidic or strongly basic conditions. Shipping at ambient temperature is acceptable for short periods when the powder remains sealed and desiccated.
Identity and purity are assessed by complementary methods rather than a single test. Reversed-phase high-performance liquid chromatography separates the peptide from related impurities and reports a percentage purity. Mass spectrometry, most often with electrospray ionization, confirms the expected molecular mass and detects sequence-related variants. Amino acid analysis can verify composition, while water content and residual counterion measurements support the mass balance of a batch. Stability studies under accelerated conditions are used to estimate shelf life, though such estimates carry uncertainty for long-term storage.
Material supplied for research use is normally a white to off-white lyophilized powder. The solid is hygroscopic and is handled in a low-humidity environment to limit water uptake. Bulk quantities are frequently shipped in sealed vials under inert gas. Once reconstituted in water or a neutral buffer, the solution is less stable than the dry powder and is usually divided into single-use aliquots.
=== Feature films === Phang's debut feature film that she directed and wrote was entitled Half-Life (2008) and it starred Sanoe Lake, Julia Nickson-Soul, Leonardo Nam, James Eckhouse, Susan Ruttan and Alexander Agate. The film premiered at the 2008 Sundance Film Festival in the New Frontiers section, and also screened at the Gen Art Film Festival (where it won a Best Feature award), the San Francisco International Asian American Film Festival (where it won a Best Narrative award), the Asian American International Film Festival (where Phang won the "Emerging Director Award"), the Fairy Tales International Gay & Lesbian Film Festival (where it won the Visionary Award), the Tokyo International Film Festival (where it was in-competition and was nominated for the Tokyo Grand Prix), the Mannheim-Heidelberg International Film Festival (where it was also in competition and nominated for the Main Award), and the International Women's Film Festival in Seoul, Korea (where it was opening night film). The film received a limited theatrical release on December 1, 2009. After Half life, Phang's follow-up project was, Look For Water, and Crazy Beats Strong Every Time. Phang received a grant from the Sundance Institute Cinereach Grant, the Sundance Annenberg Feature Film Fellowship, and the Tribeca Film Festival to support these developments. Phang's follow up film that she directed, wrote and edited was Advantageous (2015), which was based on her award-winning short film of the same name. The film starred Jacqueline Kim, Ken Jeong, James Urbaniak, Freya Adams and Samantha Kim.
Blue Shift was announced in the second quarter of 2000 as part of an upcoming Dreamcast port of Half-Life. While the port was developed by Captivation Digital Laboratories, Blue Shift was developed by Gearbox Software, who also developed the first Half-Life expansion, Opposing Force. The game had the working title Half-Life: Guard Duty; publisher Sierra Entertainment announced the name Blue Shift on August 30, 2000. As with Opposing Force, the title has a double meaning, referring to both the blue shift light phenomenon and the name of Barney's shift. The Dreamcast port would include higher detail models and textures that were double the polygon count of Valve's original Half-Life models. At the European Computer Trade Show in September 2000, information about Blue Shift's story and development direction was revealed, along with a release date of November 1, 2000, for the Dreamcast version of Half-Life. The port was delayed by Sierra to ensure the "high expectations of consumers" were met, anticipating release by the end of the year. On March 29, 2001, Sierra announced that Blue Shift would also be released for Windows as a standalone game that would not require the original Half-Life to run. The new models developed for the Dreamcast version would also be included in the PC version as the Half-Life High Definition pack, and could be applied to Half-Life and Opposing Force. At the E3 2001, Gearbox announced that Blue Shift was complete and exhibited a playable version. It was released on June 12, 2001, in North America, and on June 15 in Europe.
=== Isotope hydrology === Hydrogen and oxygen isotopes also work as tracers for water budget in terrestrial reservoirs, including lakes, rivers, groundwater and soil water. For a lake, both the amount of water in the lake and the isotopic composition of the water are determined by a balance between inputs (precipitation, stream and ground water inflow) and outputs (evaporation, stream and ground water outflow). The isotopic composition of lake water can often be used to track evaporation, which causes isotope enrichment in the lake water, as well as a δD-δ18O slope that is shallower than the meteoric water line. The isotopic composition of river water is highly variable and have complicated sources over different timescales, but can generally be treated as a two-endmember mixing problem, a base-flow endmember (mainly ground water recharge) and an overland-flow endmember (mainly storm events). The isotope data suggest that the long-term integrated base-flow endmember is more important in most rivers, even during peak flows in summer. Systematic river isotope data were collected across the world by the Global Network of Isotopes in Rivers (GNIR)[2] Archived 2016-05-13 at the Wayback Machine.The isotopic composition of groundwater can also be used to trace its sources and flow paths. An example is a groundwater isotope mapping study in Sacramento, California, which showed lateral flow of river water with a distinct isotope composition into the groundwater that developed a significant water table depression due to pumping for human use.
The purine nucleotide cycle is used in times of glycolytic or ATP crisis, such as strenuous exercise or starvation. It produces fumarate, a citric acid cycle intermediate, which enters the mitochondrion through the malate-aspartate shuttle, and from there produces ATP by oxidative phosphorylation.
Sources: en.wikipedia.org
== V == Pablo Valenzuela (b. 1941). Chilean biochemist and biotechnologist at Chiron Corporation (Emeryville, California), known for his genetic studies of hepatitis viruses. Member of the Chilean Academy of Sciences. Ruth van Heyningen (1917–2019). British biochemist at Oxford University, known for her research on the lens and cataracts. Donald Van Slyke (1883–1971). Dutch American biochemist at the Brookhaven National Laboratory noted for the measurement of gas and electrolyte levels in tissues. A unit of measurement for buffering activity, the slyke, is named after him. Member Natl. Acad. Sci. USA. John Craig Venter (1946–2026). American biotechnologist at the J. Craig Venter Institute (Rockville, Maryland), known for human genome sequencing. Member Natl. Acad. Sci. USA. Donald Voet (1938–2023). American biochemist at the University of Pennsylvania known for his textbook Biochemistry. Judith G. Voet (b. 1941). American biochemist at Swarthmore College known for her textbook Biochemistry.
=== Angular velocity === A MERU (milli Earth rate unit) is a measure of angular velocity equal to 1⁄1000 of Earth's rotation rate: 1 MERU = 7.292115×10^−8 radians per second or about 0.2625 milliradians/hour. It was introduced by MIT's Instrumentation Laboratories (now Draper Labs) to measure the performance of inertial navigation systems.
=== Restriction fragment length polymorphism === Restriction fragment length polymorphism (RFLP) is considered to be the simplest and earliest method to detect SNPs. SNP-RFLP makes use of the many different restriction endonucleases and their high affinity to unique and specific restriction sites. By performing a digestion on a genomic sample and determining fragment lengths through a gel assay it is possible to ascertain whether or not the enzymes cut the expected restriction sites. A failure to cut the genomic sample results in an identifiably larger than expected fragment implying that there is a mutation at the point of the restriction site which is rendering it protection from nuclease activity. The combined factors of the high complexity of most eukaryotic genomes, the requirement for specific endonucleases, the fact that the exact mutation cannot necessarily be resolved in a single experiment, and the slow nature of gel assays make RFLP a poor choice for high throughput analysis.
During the 2025 legislative session, Moore introduced the Housing for Jobs Act, a bill that would require local governments to automatically approve new housing developments in areas where there are 1.5 jobs for every available housing unit. After the Maryland Association of Counties expressed concerns with the bill, House lawmakers rewrote the bill that requires the state's housing secretary to set a 10-year target for housing production in the state and creates a commission to study the state's housing crisis and develop recommendations on how to address the lack of affordable housing in the state. However, this version of the bill failed to pass the General Assembly. In August 2025, Moore signed an executive order incentivizing the Maryland Department of General Services and the Maryland Department of Transportation to use their available land for housing and accelerate land awards to developers, creates housing production targets for Maryland counties, and instructs all state agencies that use housing-related permits to draft and implement plans to speed up and increase transparency around permit application processing. In January 2026, Moore said he would support three bills to spur construction and increase housing in Maryland, including proposals to encourage mixed-use development projects on state-owned land at train stations and give Maryland developers "early vesting", which would lock in a project's ground rules for five years.
== Effectiveness == Negative pressure wound therapy is usually used with chronic wounds or wounds that are expected to present difficulties while healing (such as those associated with diabetes). Negative pressure wound therapy is approved by the FDA and numerous randomized controlled trials have been conducted on this technique, however, the evidence supporting how effective NPWT is compared to standard wound care dressings is not clear. Low-level evidence indicates that there may be a lower risk of death and less surgical site infections associated with NPWT compared to standard dressing care, however there may not be a difference in the risk of wound reopening when comparing the two approaches. NPWT may increase the risk of skin blistering compared to standard wound care. NPWT may be a more cost effective approach for closing wounds following a caesarean section in women who are obese, however, NPWT is not likely as cost effective for closing wounds associated with fracture surgeries. It is not clear if NPWT is cost effective for closing wounds associated with other types of surgery. NPWT has been used to treat non-trauma patients after abdominal surgery. Non-trauma patients are people who might need surgery for conditions such as abdominal infections or cancer. However, it is still not clear how safe and effective NPWT is for treating non-trauma patients with open abdomens. For treating diabetic ulcers of the feet, "consistent evidence of the benefit of NPWT" in the treatment of diabetic ulcers of the feet has been reported.
Sources: en.wikipedia.org
Second Cup Coffee Co. is a Canadian specialty coffee retailer operating more than 345 cafes across the country. Its headquarters are in Mississauga, Ontario. Its stores sell hot and cold beverages, pastries, snacks, pre-packaged food items, hot and cold sandwiches, and drinkware, including mugs and tumblers. Second Cup sales continue to compete with Starbucks, Tim Hortons and McDonald's, which also feature espresso-based specialty drinks. Since its inception, Second Cup has expanded its franchises to the United States, Morocco, Saudi Arabia, Bahrain, Kuwait, Oman, Qatar, Lebanon, Jordan, Egypt, the United Arab Emirates, Iraq, Syria, Yemen, Cyprus, Azerbaijan, Angola, Lithuania, and Romania. It also opened a store in Pakistan in 2013, in the United Kingdom in 2014, in the Philippines in 2015, and in Poland in 2016.
A cold trap is a concept in planetary science that describes an area cold enough to freeze (trap) volatiles. Cold traps can exist on the surfaces of airless bodies or in the upper layers of an adiabatic atmosphere. On airless bodies, the ices trapped inside cold traps can potentially remain there for geologic time periods, providing a glimpse into the primordial solar system. In adiabatic atmospheres, cold traps prevent volatiles (such as water) from escaping the atmosphere into space.
Mizell led the league in strikeouts with 257, finished second in ERA to Tom Gorman (1.97 to 1.94), and tied for seventh in the league with 16 wins. With a record of 99–61, Houston won the pennant by 13.5 games over the San Antonio Missions.
taxis A directional response by a cell or a population of cells to a specific stimulus; a movement or other activity occurring in a non-random direction and dependent on the direction from which the stimulus originated. This contrasts with kinesis, a response without directional bias.
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.