A practical reference on 垂体受体: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-09-23. Anything still debated is marked as such rather than presented as settled.
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.
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。
研究背景集中在特定人群的体成分改变，尤其是与脂肪分布异常相关的内脏脂肪堆积。不同地区对它的监管状态与获批适应症并不一致，部分市场仅限特定诊断人群使用。在一般人群中的长期效应、与其他激素的相互作用以及停药后的维持情况仍属开放问题，现有数据不足以给出普遍结论。
| Property | Value | Notes |
|---|---|---|
| Drug class | Peptide hormone analog | Acts at the growth hormone-releasing hormone receptor |
| Receptor | Growth hormone-releasing hormone receptor | G protein-coupled; raises cyclic AMP in somatotrophs |
| Key mediator | Insulin-like growth factor 1 | Increases with repeated administration |
| Main studied population | Adults with HIV-associated lipodystrophy | Trials measured visceral adipose tissue by imaging |
| Route | Subcutaneous injection | Given once daily in clinical use |
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 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.
By contrast, in ParkingEye Ltd v Beavis, a majority of the Supreme Court apparently felt able to declare that the law under Unfair Terms in Consumer Contracts Directive was acte clair, and decline to make a reference, even though a senior Law Lord delivered a powerfully reasoned dissent. However, in addition to a reluctance to make references, a general scepticism has grown among senior member state judiciaries of the mode of reasoning used by the Court of Justice. The UK Supreme Court in R (HS2 Action Alliance Ltd) v Secretary of State for Transport devoted large parts of its judgment to criticism, in its view, an unpredictable 'teleological' mode of reasoning which, could decrease confidence in maintaining a dialogue within a plural and transnational judicial system. It added that it might not interpret the European Communities Act 1972 to abridge basic principles and understanding of constitutional functioning – in effect implying that it might decline to follow unreasonable Court of Justice judgments on important issues. Similarly, the German Constitutional Court in the Outright Monetary Transactions case referred a question for preliminary ruling on whether the European Central Bank's plan to buy Greek and other government bonds on secondary markets, despite the Treaty prohibition on buying them directly, was unlawful. In a highly unusual move, the two most senior judges dissented that the ECB's plan could be lawful, while the majority closely guided the Court of Justice on the appropriate mode of reasoning.
== Signs and symptoms == There are multiple symptoms that can help this disease to be diagnosed, this disease is marked by the presence of acanthocytes in blood (these acanthocytes can sometimes be absent or even make a late appearance in the course of the disease.) and neurodegeneration causing a choreiform movement disorder. Another one of them would be that this disease should be considered in patients who have elevated levels of acanthocytes in a peripheral blood film. The serum creatine kinase is often elevated in the body of the people who are affected by this disease. Choreoacanthocytosis patients may have a "rubber man" appearance with truncal instability and sudden, violent trunk spasms. Patients develop generalized chorea and a minority of Choreoacanthocytosis patients develops Parkinsonism. In a least one third of patients, seizures, typically generalized, are the first manifestation of disease. Impairment of memory and executive functions is frequent, although not invariable. People afflicted by this disease also experience a loss of neurons. Loss of neurons is a hallmark of neurodegenerative diseases. Due to the generally non-regenerative nature of neuronal cells in the adult central nervous system, this results in an irreversible and fatal process of neurodegeneration. There is also the presence of several movement related disorders including chorea, dystonia and bradykinesia, one of the more incapacitating ones includes Truncal spasms.
After creation of the dTMP molecule, another kinase, thymidylate kinase, can act upon dTMP to create the diphosphate form, dTDP. Nucleoside diphosphate kinase catalyzes production of thymidine triphosphate, dTTP, which is used in DNA synthesis. Because of this, thymidine kinase activity is closely correlated with the cell cycle and used as a tumor marker in clinical chemistry. Therefore, it can sometime be used to predict patient prognosis. Patients with mutations in the thymidine kinase gene may have a certain type of mitochondrial DNA depletion syndrome, a disease that leads to death in early childhood.
== Reception == Half-Life 2: Deathmatch was well-received upon its release, with reviewers praising its inclusion of the gravity gun. GameSpot lauded the game for the Source engine's "impressive use of physics" and the available selection of maps. IGN paid similar compliments to the title, also speaking highly of the "fast play style that [Half-Life 2: Deathmatch] produces." Multiple reviews stated that the game suffered from large amount of lag upon release, but GameSpy noted that this was remedied soon after as more servers came online.
Sources: en.wikipedia.org
=== Amino acid metabolism === Transaminases break down amino acids with PLP as a cofactor. The proper activity of these enzymes is crucial for the process of moving amine groups from one amino acid to another. To function as a transaminase coenzyme, PLP bound to a lysine of the enzyme then binds to a free amino acid via formation of a Schiff's base. The process then dissociates the amine group from the amino acid, releasing a keto acid, then transfers the amine group to a different keto acid to create a new amino acid. Serine racemase which synthesizes the neuromodulator D-serine from its enantiomer is a PLP-dependent enzyme. PLP is a coenzyme needed for the proper function of the enzymes cystathionine synthase and cystathionase. These enzymes catalyze reactions in the catabolism of methionine. Part of this pathway (the reaction catalyzed by cystathionase) also produces cysteine. Selenomethionine is the primary dietary form of selenium. PLP is needed as a cofactor for the enzymes that allow selenium to be used from the dietary form. PLP also plays a cofactor role in releasing selenium from selenohomocysteine to produce hydrogen selenide, which can then be used to incorporate selenium into selenoproteins. PLP is required for the conversion of tryptophan to niacin, so low vitamin B6 status impairs this conversion.
=== Biotransformation === n-Hexane is biotransformed to 2-hexanol and further to 2,5-hexanediol in the body. The conversion is catalyzed by the enzyme cytochrome P450 utilizing oxygen from air. 2,5-Hexanediol may be further oxidized to 2,5-hexanedione, which is neurotoxic and produces a polyneuropathy. In view of this behavior, replacement of n-hexane as a solvent has been discussed. n-Heptane is a possible alternative.
Dosages vary according to the age groups and the individual condition of the person, body weight, and compliance with the medication and diet. Other predictors of the required dosage are sex, body mass index, deiodinase activity (SPINA-GD), and etiology of hypothyroidism. Annual or semiannual clinical evaluations and TSH monitoring are appropriate after dosing has been established. Levothyroxine is taken on an empty stomach about half an hour to an hour before meals. As such, thyroid replacement therapy is usually taken 30 minutes prior to eating in the morning. For patients with trouble taking levothyroxine in the morning, bedtime dosing is effective, as well. A study in 2015 showed greater efficacy of levothyroxine when taken at bedtime. Doses of levothyroxine that normalize serum TSH may not normalize abnormal levels of LDL cholesterol and total cholesterol. Poor compliance in taking the medicine is the most common cause of elevated TSH levels in people receiving appropriate doses of levothyroxine.
=== 1971–present: the "war on drugs" === On May 27, 1971, after a trip to Vietnam, two congressmen, Morgan F. Murphy (Democrat) and Robert H. Steele (Republican), released a report describing a "rapid increase in heroin addiction within the United States military forces in South Vietnam". They estimated that "as many as 10 to 15 percent of our servicemen are addicted to heroin in one form or another." On June 6, a New York Times article, "It's Always A Dead End on 'Scag Alley'", cited the Murphy-Steele report in a discussion of heroin addiction. The article stated that, in the US, "the number of addicts is estimated at 200,000 to 250,000, only about one‐tenth of 1 per cent of the population but troublesome out of all proportion." It also noted, "Heroin is not the only drug problem in the United States. 'Speed' pills – among them, amphetamines – are another problem, and not least in the suburbs where they are taken by the housewife (to cure her of the daily 'blues') and by her husband (to keep his weight down)." On June 17, 1971, Nixon presented to Congress a plan for expanded anti-drug abuse measures. He painted a dire picture: "Present efforts to control drug abuse are not sufficient in themselves. The problem has assumed the dimensions of a national emergency. ...
=== Thyroid cancer === The US Food and Drug Administration requires a boxed warning in the package inserts of GLP-1 agonists due to the risk of thyroid C-cell tumors, including medullary thyroid cancer (MTC). GLP-1 agonists are contraindicated in people with a family or personal history of MTC or multiple endocrine neoplasia type 2. In mice, long-term use of GLP-1 agonists stimulates calcitonin secretion, leading to C-cell hypertrophy and increased risk of thyroid cancer, but no increased secretion of calcitonin has been observed in humans. A retrospective national cohort study in France reported an increased risk of thyroid cancer (all and medullary) after 1–3 years of treatment with GLP-1 agonists for diabetes, but other large retrospective studies have not reported a similar association, including with long-term use of GLP-1 agonists and over 10 years of followup.
Sources: en.wikipedia.org
Pethidine, also known as meperidine and sold under the brand name Demerol among others, is a fully synthetic opioid pain medication of the phenylpiperidine class. Synthesized in 1938 as a potential anticholinergic agent by the German chemist Otto Eisleb, its analgesic properties were first recognized by Otto Schaumann while working for IG Farben, in Germany. Pethidine is the prototype of a large family of analgesics including the pethidine 4-phenylpiperidines (e.g., piminodine, anileridine), the prodines (e.g., alphaprodine, MPPP), bemidones (e.g., ketobemidone), and others more distant, including diphenoxylate and analogues. Pethidine is indicated for the treatment of moderate to severe pain, and is delivered as a hydrochloride salt in tablets, as a syrup, or by intramuscular, subcutaneous, or intravenous injection. For much of the 20th century, pethidine was the opioid of choice for many physicians; in 1975, 60% of doctors prescribed it for acute pain and 22% for chronic severe pain. It was patented in 1937 and approved for medical use in 1943. Compared with morphine, pethidine was considered to be safer, carry a lower risk of addiction, and to be superior in treating the pain associated with biliary spasm or renal colic due to its assumed anticholinergic effects. These were later discovered to be inaccurate assumptions, as it carries an equal risk of addiction and possesses no advantageous effects on biliary spasm or renal colic compared to other opioids.
as a vasodilator in severe Raynaud's phenomenon or ischemia of a limb; in pulmonary hypertension. in primary pulmonary hypertension (PPH) The production of prostacyclin is inhibited by the action of NSAIDs on cyclooxygenase enzymes COX1 and COX2. These convert arachidonic acid to prostaglandin H2 (PGH2), the immediate precursor of prostacyclin. Since thromboxane (an eicosanoid stimulator of platelet aggregation) is also downstream of COX enzymes, one might think that the effect of NSAIDs would act to balance. However, prostacyclin concentrations recover much faster than thromboxane levels, so aspirin administration initially has little to no effect but eventually prevents platelet aggregation (the effect of prostaglandins predominates as they are regenerated). This is explained by understanding the cells that produce each molecule, TXA2 and PGI2. Since PGI2 is primarily produced in a nucleated endothelial cell, the COX inhibition by NSAID can be overcome with time by increased COX gene activation and subsequent production of more COX enzymes to catalyze the formation of PGI2. In contrast, TXA2 is released primarily by anucleated platelets, which are unable to respond to NSAID COX inhibition with additional transcription of the COX gene because they lack DNA material necessary to perform such a task. This allows NSAIDs to result in PGI2 dominance that promotes circulation and retards thrombosis. In patients with pulmonary hypertension, inhaled epoprostenol reduces pulmonary pressure, and improves right ventricular stroke volume in patients undergoing cardiac surgery.
Quotations related to Antimicrobial resistance at Wikiquote WHO fact sheet on antimicrobial resistance Animation of Antibiotic Resistance Archived 28 September 2022 at the Wayback Machine Bracing for Superbugs: Strengthening environmental action in the One Health response to antimicrobial resistance UNEP, 2023. CDC Guideline "Management of Multidrug-Resistant Organisms in Healthcare Settings, 2006"
=== Burn and wound healing center === Edlich's interest in emergency medical care was complemented by his clinical experience in burn care. After accepting the position as Director of University of Virginia Burn Center, which initially consisted of only two beds, he enlisted the help of benefactors as well as the University of Virginia to develop the 16-bed DeCamp Burn and Wound Healing Center, which included a hyperbaric oxygen treatment system for patients with necrotizing fasciitis and purpura fulminans. He helped to devise a new silver sulfadiazine cream containing poloxamer 188 that exhibits less tissue toxicity than that of the commercially available silver sulfadiazine cream. Edlich devised a new Gram stain technique for quantitative bacteriology using stable iodophors rather than unstable aqueous iodine. This reliable Gram stain technique is now being used throughout the world. When Edlich treated burn patients in which the patient's ignited clothing was adherent to the burned skin, he was concerned that the adult textiles were highly flammable and became the ignition source for the burn injury. His clinical measurements of fabric flammability of the textiles as well as a careful review of the ignition source documented that flammable liquids, such as gasoline, were the ignition sources of most burn injuries. Consequently, Edlich initiated a nationwide educational program that has dramatically reduced the frequency of burn injuries stemming from flammable liquids.
Trump threatens to impose on Iran further aggravates inflation as the oil revenues are expected to decrease and cause a further depreciation of the Iranian real. According to the world bank food security report food prices increased from April 2024 to April 2025 by 42.3% making the food inflation in the Iran the second largest in the world.
Sources: en.wikipedia.org
It is a laboratory-made peptide that mimics growth hormone-releasing hormone. It prompts the pituitary gland to release growth hormone and has been studied mainly in adults with HIV-associated lipodystrophy.
Administered growth hormone supplies the hormone directly, while this peptide acts upstream by prompting the pituitary to release it. The indirect route preserves pulsatile secretion and some endogenous feedback, which changes the hormone and IGF-1 profile observed after treatment.
Reductions in visceral adipose tissue appear consistently in randomized trials of the approved population. Effects on peripheral fat, cardiovascular outcomes, and use outside that population are less well established.
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。