垂体受体 is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2025-08-03. Where a claim depends on a specific study, the study is described rather than over-claimed.
Tesamorelin is a synthetic analog of growth hormone-releasing hormone, a peptide hormone produced by the hypothalamus. The molecule retains the 44-amino-acid sequence of human GHRH and carries a trans-3-hexenoyl modification at its N-terminus. This modification increases resistance to enzymatic degradation and extends the peptide's functional stability relative to native GHRH. The compound is supplied as a lyophilized powder for reconstitution and subcutaneous administration in clinical settings. Its development code was TH9507, and it belongs to the GHRH analog class. It is not a growth hormone product; instead, it acts upstream to stimulate endogenous growth hormone release.
Clinical interest in tesamorelin arose from the need to address visceral adiposity in people living with HIV. Antiretroviral therapy improved survival but was associated in some patients with central fat accumulation, altered lipid profiles, and metabolic complications. This condition, often called HIV-associated lipodystrophy, involves excess visceral adipose tissue that is difficult to manage through diet and exercise alone. Investigators evaluated tesamorelin because GHRH analogs can stimulate growth hormone secretion and influence fat distribution without direct liposuction or invasive procedures.
A Phase 3 program led to regulatory approval in the United States in 2010 for reduction of excess visceral abdominal fat in adults with HIV and lipodystrophy. Subsequent studies examined effects on liver fat, muscle area, and metabolic markers, with mixed findings for some endpoints. Long-term cardiovascular outcomes and effects on mortality remain uncertain because most trials were relatively short and focused on imaging-based fat measurements. Use in populations without HIV has been studied experimentally but is not part of the approved indication.
tesamorelin 是一种人工合成的四十四肽，序列与内源性生长激素释放激素（GHRH）的 1-44 片段一致，区别在于 N 端加接了一个反式-3-己烯酰基。该修饰抑制二肽基肽酶 IV 的快速切割，从而延长分子在循环中的存留时间。作为肽类分子，它难以经胃肠道吸收，文献中讨论的均是注射途径。分类上通常把它归为 GHRH 类似物，以区别于生长激素本身。
作用位置在垂体前叶。tesamorelin 与 GHRH 受体结合后激活腺苷酸环化酶，升高细胞内 cAMP，再经蛋白激酶 A 通路促进生长激素的合成与释放。由于它作用于内源调控节点，生长激素仍以脉冲方式分泌，而不是被持续抬升到固定水平。生长激素随后在肝脏等组织诱导胰岛素样生长因子 1 产生，构成完整的生长激素轴响应。
| Property | Value | Notes |
|---|---|---|
| Molecular weight | Approximately 5,136 Da | Based on the 44-amino-acid peptide backbone and N-terminal modification. |
| Appearance | White to off-white lyophilized powder | Usually supplied in single-use vials for reconstitution. |
| Solubility | Freely soluble in water; slightly soluble in some organic solvents | Peptide nature supports aqueous reconstitution. |
| Typical storage | 2–8 °C, protected from light | Refrigeration reduces degradation; avoid freezing unless specified. |
| Common analytical method | Reverse-phase high-performance liquid chromatography | Used for identity, purity, and quantification. |
| Synonyms | Tesamorelin, TH9507, GHRH(1-44) analog | Generic descriptors; avoid proprietary names. |
Tesamorelin is a synthetic peptide that acts as an analog of growth hormone-releasing hormone, a natural hypothalamic signal. Its sequence corresponds to the forty-four amino acid form of the human hormone, with a small acyl group attached near the amino terminus. That modification slows enzymatic breakdown and extends the time the peptide remains active in circulation. The compound was developed as a pharmacological way to raise endogenous growth hormone output rather than supplying the hormone directly.
After injection, the peptide binds receptors on somatotroph cells in the anterior pituitary. Receptor activation raises intracellular cyclic AMP and triggers release of stored growth hormone into the bloodstream. Because the compound works through the body's own regulatory system, growth hormone pulses retain much of their normal feedback control. Repeated administration also raises insulin-like growth factor 1, a hormone produced mainly in the liver. Investigators treat that rise as a marker that the pituitary axis has been engaged.
nuclear matrix Also nucleoskeleton. A mesh-like latticework of protein polymers and microfilaments suspended in the nucleoplasm in the nuclei of eukaryotic cells, akin to the cytoskeleton in the cytoplasm. The nuclear matrix functions as a scaffold and an anchor for large DNA molecules such as chromosomes and for the macromolecular complexes that perform essential nuclear activities such as transcription and DNA replication.
==== Quantification ==== Polyphenolic content in vitro can be quantified by volumetric titration. An oxidizing agent, permanganate, is used to oxidize known concentrations of a standard tannin solution, producing a standard curve. The tannin content of the unknown is then expressed as equivalents of the appropriate hydrolyzable or condensed tannin. Some methods for quantification of total polyphenol content in vitro are based on colorimetric measurements. Some tests are relatively specific to polyphenols (for instance the Porter's assay). Total phenols (or antioxidant effect) can be measured using the Folin–Ciocalteu reaction. Results are typically expressed as gallic acid equivalents. Polyphenols are seldom evaluated by antibody technologies. Other tests measure the antioxidant capacity of a fraction. Some make use of the ABTS radical cation which is reactive towards most antioxidants including phenolics, thiols and vitamin C. During this reaction, the blue ABTS radical cation is converted back to its colorless neutral form. The reaction may be monitored spectrophotometrically. This assay is often referred to as the Trolox equivalent antioxidant capacity (TEAC) assay. The reactivity of the various antioxidants tested are compared to that of Trolox, which is a vitamin E analog. Other antioxidant capacity assays which use Trolox as a standard include the diphenylpicrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC), ferric reducing ability of plasma (FRAP) assays or inhibition of copper-catalyzed in vitro human low-density lipoprotein oxidation.
=== Nucleus === Granzyme B has many substrates located in the nucleus. Granzyme B can cleave PARP (poly ADP ribose polymerase) and DNA PK (DNA protein kinase) to disrupt DNA repair and retroviral DNA integration. Granzyme B can also cleave nucleophosmin, topoisomerase 1 and nucleolin to prevent viral replication. Granzyme B can cleave ICP4 from the HSV 1 virus which is an essential protein used for gene transactivation and NUMA (Nuclear mitotic apparatus protein) can be cleaved to prevent mitosis. Granzyme B can also cleave DBP (DNA Binding Protein) into a 50 kDa fragment and then into an additional 60 kDa indirectly through the caspases it activates.
Sources: en.wikipedia.org
The Ba'athist government of Syria ruled by the Al-Assad family was known for its extensive involvement in drug trade since the 1970s. As of 2022, the Syrian government financed the biggest multi-billion dollar drug trade in the world, mostly focused on an illegal drug known as Captagon, making it the world's largest narco-state. Its revenues from Captagon smuggling alone were estimated at $57 billion annually in 2022, which is approximately thrice the total trade of all Mexican cartels. General Maher al-Assad, younger brother of Syrian dictator Bashar al-Assad and commander of the Fourth Armoured Division, directly supervised the production, smuggling and profiteering of the drug business. Already suffering from severe financial problems as a result of corruption and civil war, profits from Captagon were said to be the "lifeline" of the Assad regime, through which it earned more than 90% of its total revenue. The smugglers receive direct training from the Syrian military to successfully conduct trafficking operations. Republican Guard, commanded by Maher al-Assad was one of the main Ba'athist military divisions that was engaged in perpetrating brutal crackdowns and mass violence against protestors across the country. In 2018, Bashar al-Assad assigned Maher as the commander of the 4th Armoured Division, a military unit that supervised the Assad regime's criminal enterprises like smuggling, drug trafficking, narcotics production and plunder of goods and resources.
Media related to Structural biology at Wikimedia Commons Nature: Structural & Molecular Biology magazine website Journal of Structural Biology Structural Biology - The Virtual Library of Biochemistry, Molecular Biology and Cell Biology Structural Biology in Europe Learning Crystallography
==== Insects and invertebrates ==== Most bats, especially in temperate areas, prey on insects. The diet of an insectivorous bat may span many species, including flies, mosquitos, beetles, moths, grasshoppers, crickets, termites, bees, wasps, mayflies and caddisflies. They will also eat other arthropods such as spiders, scorpions, centipedes, lobsters and shrimp. Large numbers of Mexican free-tailed bats (Tadarida brasiliensis) fly hundreds of metres above the ground in central Texas to feed on migrating moths. Species that hunt insects in flight, like the little brown bat (Myotis lucifugus) and the eastern red bat (Lasiurus borealis), may catch an insect in mid-air directly with the mouth or use their tail membranes or wings. The slow-moving brown long-eared bat (Plecotus auritus) plucks insects from vegetation, while many horseshoe bat species wait for them from their perches. Some bats may take the insect to their roost and eat it there. Arthropod-eating bats living at high latitudes have to consume prey with higher energetic value than tropical bats.
Sources: en.wikipedia.org
1994: Ong Yeow Tian, a Singaporean hairstylist who was hanged on 25 November 1994 for murdering a police officer and shooting two other cops in 1989. 1995: Ng Theng Shuang, a Malaysian national, hanged on 14 July 1995 for discharging a firearm with intent to cause injury, after shooting 3 people during the attempted robbery of Tin Sing Goldsmiths in South Bridge Road in 1992. 1997: Lim Chwee Soon, hanged on 25 July 1997 for discharging a firearm seven times during the robbery of the Kee Hing Hung Rolex boutique at the People's Park Complex in 1995. 2001: Tay Chin Wah, a Singaporean taxi driver, was arrested for an unsolved 1995 case of shooting two men. He was sentenced to death on 21 February 2001, and hanged on 26 October 2001. 2006: Khor Kok Soon, one of Singapore's top ten fugitives, was charged in 2004 for firing a gun at 43-year-old police sergeant Lim Kiah Chin (who escaped unharmed) in 1984. He was sentenced to death in February 2005, and eventually hanged. Khor was also alleged to have killed 25-year-old truck driver Ong King Hock. 2006: Lim Thian Lai, a Singaporean gunman who was caught in 2004 for murdering an illegal moneylender Tan Tiong Huat back in 1997. Lim was found guilty of discharging a firearm and killing Tan by shooting, and sentenced to death in May 2005. He lost his appeal in September 2005 and had since been hanged. 2009: Tan Chor Jin, alias Tony Kia, nicknamed the "One-eyed Dragon" in Singapore media, was executed on 9 January 2009 for illegally discharging a firearm and killing 41-year-old nightclub owner Lim Hock Soon by shooting.
== Education and professional development == The HGSA oversees professional training and certification in the fields of Diagnostic Genomics and Genetic Counseling. Two Boards of Censors oversee training in these two respective fields. The HGSA partners with the Royal College of Pathologists of Australasia to train senior diagnostic genomicists to become Fellows of the Faculty of Science. The Australasian Association of Clinical Geneticists (AACG), a Special Interest Group of the HGSA, has direct ties with the Royal Australasian College of Physicians (RACP), which is the body that oversees training and accreditation in clinical genetics in Australasia. The AACG advises the RACP on curricula and training requirements. In addition, members of the AACG supervise the clinical training of RACP trainees in clinical genetics. The AACG also oversees a lecture series for clinical genetics trainees. The HGSA hosts a large number of educational events throughout the year to help members undertake continuing professional development. In addition to the Society's Annual Scientific Meeting, members have access to a large number of webinars that are broadcast across Australia and New Zealand. Furthermore, each Branch holds face-to-face educational activities, such as lectures and symposia, for local members.
=== Musculoskeletal system === Amyloid proteins deposit most commonly inside the knee, followed by hands, wrists, elbow, hip, and ankle, causing joint pain. In males with advanced age (>80 years), there is significant risk of wild-type transthyretin amyloid deposition in synovial tissue of knee joint, but predominantly in old age deposition of wild type transthyretin is seen in cardiac ventricles. ATTR deposits have been found in ligamentum flavum of patients that underwent surgery for lumbar spinal stenosis. In beta 2-microglobulin amyloidosis, males have high risk of getting carpal tunnel syndrome. Aβ2MG amyloidosis (Hemodialysis associated amyloidosis) tends to deposit in synovial tissue, causing chronic inflammation of the synovial tissue in knee, hip, shoulder and interphalangeal joints. Amyloid light chains deposition in shoulder joint causes enlarged shoulders, also known as "shoulder pad sign". Amyloid light chain depositions can also cause bilateral symmetric polyarthritis. The deposition of amyloid proteins in the bone marrow without causing plasma cell dyscrasias is called amyloidoma. It is commonly found in cervical, lumbar, and sacral vertebrae. Those affected may be presented with bone pain due to bone lysis, lumbar paraparesis, and a variety of neurological symptoms. Vertebral fractures are also common.
Mianserin appears to exert its effects via antagonism of histamine and serotonin receptors, and inhibition of norepinephrine reuptake. More specifically, it is an antagonist/inverse agonist at most, if not all sites of the histamine H1 receptor, serotonin 5-HT1D, 5-HT1F, 5-HT2A, 5-HT2B, 5-HT2C, 5-HT3, 5-HT6, and 5-HT7 receptors, and adrenergic α1- and α2-adrenergic receptors, and additionally a norepinephrine reuptake inhibitor. As an H1 receptor inverse agonist with high affinity, mianserin has strong antihistamine effects (e.g., sedation). Conversely, it has low affinity for the muscarinic acetylcholine receptors, and hence lacks anticholinergic properties. Mianserin has been found to be a low affinity but potentially significant partial agonist of the κ-opioid receptor (Ki = 1.7 μM; EC50 = 0.53 μM), similarly to some tricyclic antidepressants (TCAs). Blockade of the H1 and possibly α1-adrenergic receptors has sedative effects, and also antagonism of the 5-HT2A and α1-adrenergic receptors inhibits activation of intracellular phospholipase C (PLC), which seems to be a common target for several different classes of antidepressants. By antagonizing the somatodendritic and presynaptic α2-adrenergic receptors, which function predominantly as inhibitory autoreceptors and heteroreceptors, mianserin disinhibits the release of norepinephrine, dopamine, serotonin, and acetylcholine in various areas of the brain and body.
Sources: en.wikipedia.org
It is a synthetic peptide analog of human growth hormone-releasing hormone. It is used clinically to reduce excess visceral abdominal fat in adults with HIV-associated lipodystrophy. It works by stimulating pituitary growth hormone release.
Pivotal trials enrolled adults with HIV and excess visceral abdominal fat, often in the context of antiretroviral therapy. Participants were assessed mainly by computed tomography for visceral adipose tissue. The approved indication remains specific to that population.
Long-term effects on cardiovascular events, mortality, and sustained fat distribution are not well established. Most trials measured changes over months rather than years. Open questions also include whether benefits persist after treatment stops.
tesamorelin 属 GHRH 类似物，作用于垂体受体以促进内源生长激素释放；生长激素本身是直接补充的外源激素。两者在给药逻辑、作用位点和反馈调控路径上并不相同。