If you have been reading about GHRH analog and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-03-21. Where a claim depends on a specific study, the study is described rather than over-claimed.
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。
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。
Published work tends to frame tesamorelin as a tool for studying the GHRH axis and as a compound with measurable effects on body composition. Reports often describe visceral adipose tissue as an endpoint, assessed by imaging rather than by inference. Analytical sections commonly describe liquid chromatography with tandem mass spectrometry to confirm identity and purity, because immunoassays may cross-react with related fragments. Where results diverge between studies, differences in assay choice, sampling timing, and population are frequent explanations offered. Whether effects persist after treatment stops remains an open question.
Tesamorelin binds the growth hormone–releasing hormone receptor on pituitary somatotroph cells. The receptor signals through the Gs protein, raising intracellular cAMP and activating protein kinase A. That cascade triggers release of stored growth hormone in pulses rather than a steady stream. Because the drug acts at the receptor that normally controls this process, its effect depends on the body's own signaling architecture rather than on a synthetic pathway. The resulting hormone profile reflects the timing of each pulse, not only its size.
| 性质 | 取值 | 备注 |
|---|---|---|
| 分子类型 | 合成四十四肽 | GHRH 类似物 |
| N 端修饰 | 反式-3-己烯酰基 | 延缓酶切 |
| 分子量 | 约 5135 Da | 依序列与修饰 |
| 受体靶点 | 垂体 GHRH 受体 | 经 cAMP 通路 |
| 常见同义名 | GHRH(1-44) 类似物 | 文献通用称法 |
Signaling begins at the GHRH receptor, a class B G protein-coupled receptor displayed on somatotroph cells of the anterior pituitary. Receptor occupancy activates Gs proteins, which raise adenylyl cyclase activity and intracellular cyclic AMP, in turn driving protein kinase A dependent pathways. The downstream output is synthesis and pulsatile secretion of growth hormone into the bloodstream. Hepatic tissue and peripheral sites respond by increasing insulin-like growth factor 1 production. Somatostatin and IGF-1 itself supply negative feedback that caps the size and duration of each secretory burst.
Metabolic interest in this compound centers on fat distribution rather than on hormone levels alone. Imaging trials in adults with excess abdominal fat report reductions in visceral adipose tissue, while subcutaneous depots change comparatively little. Growth hormone and IGF-1 are presumed to carry the effect, but the separate contribution of each is not firmly established. Whether these changes persist after treatment stops, and whether they alter longer-term health outcomes, remain open questions that published work does not answer consistently.
The peptide is supplied as a lyophilized powder in single-use vials and is normally kept refrigerated between two and eight degrees Celsius, protected from light. Once dissolved, the solution is handled carefully because peptide bonds and the acyl modification can degrade under warm or alkaline conditions. Vials are inspected for cracks, and the powder is checked for color and uniformity before handling. Temperature excursions during shipping are a frequent reason for quality questions.
Identity and purity are assessed with reversed-phase high-performance liquid chromatography, which separates the peptide from truncated or oxidized forms. Mass spectrometry confirms the expected molecular weight, and peptide mapping after enzymatic digestion verifies the amino acid sequence. Water content is measured because residual moisture affects stability, and tests for aggregates or particulates are standard for injectable peptides. Circular dichroism can indicate whether the molecule has adopted an unexpected secondary structure in solution.
Tesamorelin is a synthetic peptide of 44 amino acids that reproduces the sequence of human growth hormone-releasing hormone (GHRH) and carries a trans-3-hexenoyl group on its N-terminal tyrosine. That small fatty-acid modification blocks cleavage by dipeptidyl peptidase-4, the enzyme that rapidly degrades native GHRH in plasma. The result is a molecule with a longer circulating half-life than the natural hormone while retaining the same receptor target. It is supplied as a lyophilized powder for reconstitution and belongs to the broader class of GHRH analogs studied for effects on pituitary growth hormone secretion.
Development work on the compound, originally designated TH9507, focused on conditions in which reduced growth hormone signaling is thought to contribute to altered body composition. The United States Food and Drug Administration approved it in 2010 for the treatment of excess visceral abdominal fat in adults with human immunodeficiency virus infection and lipodystrophy. Later research examined other populations, including adults with mild cognitive impairment, where a large trial did not meet its primary endpoints. This mixed record illustrates how a single mechanism can produce clear effects in one setting and inconclusive results in another.
Several related peptides act on the same receptor, including sermorelin, a shorter GHRH fragment, and modified analogs such as CJC-1295 and modified GRF(1-29) that are common in research settings rather than approved products. Tesamorelin differs from growth hormone itself in that it acts upstream, prompting the pituitary to release the hormone through physiological signaling rather than supplying it directly. Terminology in the literature distinguishes GHRH analogs, growth hormone secretagogues, and recombinant growth hormone, although popular discussion often blurs these categories together. Precise naming matters when comparing study results.
Binding of tesamorelin to the growth hormone-releasing hormone receptor on anterior pituitary somatotrophs activates a Gs protein pathway, raises cyclic AMP, and triggers release of stored growth hormone into the bloodstream. Because the analogue resists dipeptidyl peptidase-4, its plasma residence time exceeds that of native GHRH, producing a larger and more sustained secretory signal. The released growth hormone then acts on the liver and peripheral tissues to raise insulin-like growth factor 1, which feeds back on the hypothalamus and pituitary. This axis explains both the intended effects on fat distribution and the biological markers used to track them.
Studies of the compound rely on imaging and laboratory endpoints rather than on symptoms alone. Visceral adipose tissue is usually quantified by computed tomography or magnetic resonance imaging at the level of the abdomen, with waist circumference serving as a cheaper but less specific proxy. Blood work tracks insulin-like growth factor 1, fasting glucose, glycated hemoglobin, and lipid fractions. In the pivotal trials the imaging endpoint fell by roughly fifteen to twenty percent over six months, subcutaneous fat changed little, and the visceral fat returned toward baseline after treatment stopped, a pattern that shapes how clinicians discuss durability.
==== Benzamides ==== Amisulpride (Socian) ‡ – Selective dopamine antagonist. Higher doses (greater than 400 mg) act upon post-synaptic dopamine receptors resulting in a reduction in the positive symptoms of schizophrenia, such as psychosis. Lower doses, however, act upon dopamine autoreceptors, resulting in increased dopamine transmission, improving the negative symptoms of schizophrenia. Lower doses of amisulpride have also been shown to have antidepressant and anxiolytic effects in non-schizophrenic patients, leading to its use in dysthymia and social phobias. Nemonapride † – Used in Japan. Remoxipride # – Has a risk of causing aplastic anaemia and, hence, has been withdrawn from the market worldwide. It has also been found to possess relatively low (virtually absent) potential to induce hyperprolactinaemia and extrapyramidal symptoms, likely attributable to its comparatively weak binding to (and, hence, rapid dissociation from) the D2 receptor. Sultopride – An atypical antipsychotic of the benzamide chemical class used in Europe, Japan, and Hong Kong for the treatment of schizophrenia. It was launched by Sanofi-Aventis in 1976. Sultopride acts as a selective D2 and D3 receptor antagonist.
=== Dietary therapy === Initial attempts at dietary therapy in ALD involved restricting the intake of very-long chain fatty acids (VLCFA). Dietary intake is not the only source for VLCFA in the body, as they are also synthesized endogenously. This dietary restriction did not impact the levels of VLCFA in plasma and other body tissues. After the realization that endogenous synthesis was an important contribution to VLCFA in the body, efforts at dietary therapy shifted to inhibiting these synthetic pathways in the body. The parents of Lorenzo Odone, a boy with ALD, spearheaded efforts to develop a dietary treatment to slow the progression of the disease. They developed a mixture of unsaturated fatty acids (glycerol trioleate and glyceryl trierucate in a 4:1 ratio), known as Lorenzo's oil that inhibits elongation of saturated fatty acids in the body. Supplementation with Lorenzo's oil has been found to normalize the VLCFA concentrations in the body, although its effectiveness at treating the cerebral manifestations of the disease is still controversial and unproven. Trials with Lorenzo's oil have shown that it does not stop the neurological degradation in symptomatic patients, nor does it improve adrenal function, but asymptomatic patients, and speculatively AMN variants without cerebral involvement, as well as female carriers may benefit from early intake of oleic and erucic acids in addition to VLCFA restriction.
==== Small nuclear RNA ==== Small nuclear RNA (snRNA) combines with proteins to form the spliceosome in the nucleus. The spliceosome is responsible for sensing and cutting introns out of pre-mRNA, which is one of the first steps of mRNA processing. The spliceosome is a large macromolecular complex. Quaternary structure allows snRNA to detect mRNA sequences that need to be excised.
=== Interspecific predatory relationships === Over much of their range, American black bears are assured scavengers that can intimidate, using their large size and considerable strength, and if necessary dominate other predators in confrontations over carcasses. However, on occasions where they encounter Kodiak or grizzly bears, the larger two brown subspecies dominate them. American black bears tend to escape competition from brown bears by being more active in the daytime and living in more densely forested areas. Violent interactions, resulting in the deaths of American black bears, have been recorded in Yellowstone National Park. American black bears do occasionally compete with cougars over carcasses. Like brown bears, they will sometimes steal kills from cougars. One study found that both bear species visited 24% of cougar kills in Yellowstone and Glacier National Parks, usurping 10% of the carcasses. Another study found that American black bears visited 48% of cougar kills in summer in Colorado and 77% of kills in California. As a result, the cats spend more time killing and less time feeding on each kill. American black bear interactions with gray wolves are much rarer than with brown bears, due to differences in habitat preferences. The majority of American black bear encounters with wolves occur in the species' northern range, with no interactions being recorded in Mexico. Despite the American black bear being more powerful on a one-to-one basis, packs of wolves have been recorded to kill black bears on numerous occasions without eating them.
Research into the clinical use of a recombinant form of human Activated Protein C (rhAPC) known as Drotrecogin alfa-activated, branded Xigris by Eli Lilly and Company, has been surrounded by controversy. Eli Lilly ran an aggressive marketing campaign to promote its use for people with severe sepsis and septic shock and sponsored the 2004 Surviving Sepsis Campaign Guidelines. However, a 2012 Cochrane review found that its use cannot be recommended since it does not improve survival and increases bleeding risk. In October 2011, Xigris was withdrawn from the market by Eli Lilly due to a higher mortality in a trial among adults.
Sources: en.wikipedia.org
==== Earliest research ==== Charles P. Slichter wrote that "In 1955, Redfield showed that the conventional theory of saturation did not properly account for the experimental facts of nuclear resonance in solids...[Redfield] showed that the conventional approach essentially defied the second law of thermodynamics." Redfield studied NMR with Charles Pence Slichter, assisting with early superconductivity experiments at University of Illinois, Urbana and published the Redfield Theory as a postdoc under Nicolaas Bloembergen at Harvard. At first he studied electron removal in argon, hydrogen and crypton, and the movement of electrons in photoconductors, including his doctoral thesis on the Hall effect in diamonds and salt crystals. After his breakthrough work on relaxation theory, he continued to produce papers on nuclear spin relaxation.
The peculiarity of this invention compared to former treatment approaches for treating sleep disorders is the so far unknown therapeutic efficacy of (R)-phenylpiracetam, which is presumably based at least in part on the newly identified activity of (R)-phenylpiracetam as the dopamine re-uptake inhibitor Both enantiomers of phenylpiracetam, (R)-phenylpiracetam and (S)-phenylpiracetam, have been described in peer-reviewed research as dopamine transporter (DAT) inhibitors in rodents, confirming the patent claim. Their actions at the norepinephrine transporter (NET) vary: (R)-phenylpiracetam acts as a dual norepinephrine–dopamine reuptake inhibitor (NDRI), with 11-fold lower affinity for the NET than for the DAT, whereas the (S)-enantiomer is selective for the DAT. However, whereas (R)-phenylpiracetam stimulates locomotor activity, (S)-phenylpiracetam does not do so. This kind of variation in effects has also been seen with other dopamine reuptake inhibitors. Other atypical dopamine reuptake inhibitors include modafinil, mesocarb (Sydnocarb), and solriamfetol.
==== Discontinuation ==== If lithium is stopped suddenly, there is a 50% risk of sudden mania within one month of stopping. In the first year after discontinuation of lithium, there is up to a 20-fold increase in the rate of suicide or attempted suicide compared to lithium maintenance. If discontinuing lithium, it is recommended to taper it gradually and in a controlled fashion. Gradual tapering has been shown to lower the risk of relapse and suicidal events. In patients gradually tapering off the medication, discontinuation symptoms including irritability or restlessness, and somatic symptoms like vertigo, dizziness, or lightheadedness may occur. Discontinuation symptoms are generally mild and self-limiting within weeks.
The number average molecular mass of a polymer can be determined by gel permeation chromatography, viscometry via the (Mark–Houwink equation), colligative methods such as vapor pressure osmometry, end-group determination or proton NMR. High number-average molecular mass polymers may be obtained only with a high fractional monomer conversion in the case of step-growth polymerization, as per the Carothers' equation.
Sources: en.wikipedia.org
A dosage of two to six 100 μg/day transdermal estradiol patches can achieve mean levels of estradiol in the area of 200 to 400 pg/mL and can be used as a form of high-dose estrogen therapy, for instance to suppress testosterone levels in the treatment of prostate cancer in men and in feminizing hormone therapy for transgender women. High-dose transdermal estradiol patches have also been studied in the treatment of postpartum depression and postpartum psychosis; in one such study, 200, 400, and 800 μg/day estradiol in the form of transdermal patches resulted in estradiol levels of 286 pg/mL, 675 pg/mL, and 1032 pg/mL, respectively. In another study, estradiol levels with 800 μg/day estradiol in the form of transdermal patches (Estraderm TTS) resulted in estradiol levels of 690 to 815 pg/mL. However, there is erratic absorption and considerable variation in estradiol levels using high-dose estradiol patches both between and within individuals, with one study finding that estradiol levels ranged from 70 pg/mL to 1,045 pg/mL (mean 460.7 pg/mL) with six 100 μg/day estradiol patches. The Prostate Adenocarcinoma: TransCutaneous Hormones (PATCH) study is a randomized controlled trial of high-dose transdermal estradiol patches versus gonadotropin-releasing hormone agonist monotherapy in the treatment of prostate cancer in approximately 2,200 men. It is specifically comparing three to four 100 μg/day estradiol patches (FemSeven) against goserelin implants. The study was started in March 2006 and is estimated for completion in August 2021.
Additionally, the increased levels of P4 can also cause side effects such as weight gain, fatigue, and mood swings (extreme or rapid changes in mood). In prostate cancer, removal of testicular T through castration (surgical or chemical removal or inactivation of testicles) helps eliminate the growth-promoting effects of androgens. However, in some cases, metastatic tumors can develop into castration-resistant prostate cancer (CRPC). While castration reduces serum T levels by 90-95%, it only decreases DHT in the prostate gland by 50%. This difference between the magnitude of androgen levels confirms that the prostate has enzymes capable of producing DHT even without testicular T. In addition to DHT production within the prostate, researchers found that 11-oxygenated androgens play a role in maintaining total circulating androgen pool levels which are relevant to the amounts of clinically significant androgens in the body. These 11-oxygenated androgens contribute greatly to reactivating androgen signaling in patients with CRPC. 11-oxygenated androgens make up around 60% of the total active androgen pool in such patients. Unlike T or DHT, these levels of 11-oxygenated androgens remain unaffected by castration therapy.
The AST/ALT ratio increases in liver functional impairment. In alcoholic liver disease, the mean ratio is 1.45, and mean ratio is 1.33 in post necrotic liver cirrhosis. Ratio is greater than 1.17 in viral cirrhosis, greater than 2.0 in alcoholic hepatitis, and 0.9 in non-alcoholic hepatitis. Ratio is greater than 4.5 in Wilson disease or hyperthyroidism.
Sources: en.wikipedia.org
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。
作为多肽，它难以通过胃肠道吸收，通常需要注射给药。口服会因消化酶降解而失去活性，因此文献中讨论的都是注射途径。
公开研究多集中在内脏脂肪、体成分分布以及与生长激素轴相关的代谢指标。长期安全性和在普通人群中的适用性尚缺乏一致结论。
It acts on the growth hormone–releasing hormone receptor, a Gs-coupled receptor found on pituitary somatotroph cells. Activation raises cAMP and prompts pulsatile hormone release.