nuclear receptor comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2026-06-24. Numbers and descriptions here follow the published literature rather than marketing material.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ, also called NR1D1 and NR1D2. These receptors help regulate circadian rhythms and metabolic gene programs. The compound was developed for laboratory research, not as an approved therapeutic. Its identity is distinct from steroid hormones and selective androgen receptor modulators. Scientific interest centers on how REV-ERB activation changes gene expression in cells and animal models.
At the molecular level, SR9009 binds the ligand-binding domain of REV-ERB and strengthens recruitment of corepressor proteins such as NCoR and HDAC3. This increases repression of target genes, including Bmal1 and other clock-controlled and metabolic genes. In rodent studies, such changes have been linked to altered lipid handling, glucose metabolism, and energy expenditure. The precise chain of events between receptor binding and whole-body effects remains an active area of research. Findings in animals do not automatically translate to humans.
SR9009 is not approved as a medicine by major regulatory agencies. It is commonly sold as a research chemical, a category that may fall outside customary drug approval and quality rules. In sports, the World Anti-Doping Agency lists SR9009 as a prohibited substance. Athletes who use it can face sanctions if it is detected in a sample. Legal status varies by country, and importation may be restricted. Enforcement practices differ across borders.
Detection of SR9009 in biological samples usually employs liquid chromatography coupled with tandem mass spectrometry. This method can identify the parent compound and sometimes metabolites in urine or blood. Because exposure can be low and clearance may be rapid, sample timing and limits of detection matter. Laboratories validate assays for sensitivity and specificity. Results are interpreted alongside chain-of-custody and quality-control records. Urine is the common matrix for anti-doping analysis, while blood may be used in research settings.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic small molecule | Studied as a REV-ERB agonist |
| Molecular formula | C20H24ClN3O4S | Reported for the neutral compound |
| Appearance | Off-white to pale yellow solid | Typical research-grade material |
| Solubility | Sparingly soluble in water | Soluble in solvents such as DMSO |
| Common synonyms | SR9009; Stenabolic | Stenabolic is an informal alias |
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. It is not an approved medicine and has no established human therapeutic use. The compound appears in scientific literature as a tool for probing circadian and metabolic regulation. Online sellers often label it as a research chemical, sometimes using the nickname Stenabolic. Its chemical identity is distinct from selective androgen receptor modulators, stimulants, and peroxisome proliferator-activated receptor delta agonists. Researchers use it mainly in cell and animal experiments.
At the molecular level, SR9009 binds REV-ERBα and REV-ERBβ and alters their repressive activity on target genes. These nuclear receptors help regulate the circadian clock, lipid synthesis, glucose metabolism, and inflammatory pathways. By changing transcription, the compound can shift the timing or magnitude of downstream metabolic processes in model systems. It does not act through androgen receptors or adenosine receptors, which distinguishes it from several substances sold for athletic performance. Whether the same transcriptional changes occur in humans at tolerable exposures remains an open question because controlled human studies are lacking.
SR9009 is generally described as poorly soluble in water and more soluble in organic solvents such as dimethyl sulfoxide and ethanol. Stock solutions are commonly prepared in an organic solvent before dilution into an aqueous buffer or vehicle. Precipitation can occur if the organic fraction is reduced too quickly or if the final concentration exceeds the compound's solubility limit. Sonication or gentle warming may aid dissolution in some protocols, but excessive heat can promote degradation. Container material and pH can also influence observed solubility.
For long-term storage, SR9009 is typically kept as a solid at low temperature, protected from moisture and light. Desiccated conditions limit hydrolysis, while opaque containers reduce photochemical breakdown. Solutions are less stable than solids and are often stored frozen in aliquots to avoid repeated freeze-thaw cycles. Stability data are not standardized across all suppliers, so users should rely on certificate-of-analysis information when available. Degradation may appear as color change, precipitate, or decreased chromatographic purity.
Agrobacterium tumefaciens is the causal agent of crown gall disease (the formation of tumours) in over 140 species of eudicots. It is a rod-shaped, Gram-negative soil bacterium. Symptoms are caused by the insertion of a small segment of DNA (known as T-DNA, for 'transfer DNA', not to be confused with tRNA that transfers amino acids during protein synthesis), from a plasmid into the plant cell, which is incorporated at a semi-random location into the plant genome. Plant genomes can be engineered by use of Agrobacterium for the delivery of sequences hosted in T-DNA binary vectors. Agrobacterium tumefaciens is an Alphaproteobacterium of the family Rhizobiaceae, which includes the nitrogen-fixing legume symbionts. Unlike the nitrogen-fixing symbionts, tumor-producing Agrobacterium species are pathogenic and do not benefit the plant. The wide variety of plants affected by Agrobacterium makes it of great concern to the agriculture industry. Economically, A. tumefaciens is a serious pathogen of walnuts, grape vines, stone fruits, nut trees, sugar beets, horseradish, and rhubarb, and the persistent nature of the tumors or galls caused by the disease make it particularly harmful for perennial crops. Agrobacterium tumefaciens grows optimally at 28 °C (82 °F). The doubling time can range from 2.5–4h depending on the media, culture format, and level of aeration. At temperatures above 30 °C (86 °F), A. tumefaciens begins to experience heat shock which is likely to result in errors in cell division.
Ketamine is the most widely anesthetic agent used for longer duration operations. After an intravenous therapy, which is about 2.2 mg/kg, mixed with the 1.1 mg/kg xylazine the half-life of xylazine is approximately 66 minutes and the clearance is around 31 mL/kg/min when patients are halothane-anesthetized. If only managing the xylazine and ketamine, the terminal half-life will be 42 minutes and its clearance will be 27 mL/kg/min. When the CRI of ketamine is kept stable for an hour at 2.4 mg/kg/h, the terminal half-life will be 46 minutes and the clearance will be 32 mL/kg/min.
== Mechanism of action == The mechanism of action of methyldopa is not fully clear. It may reduce the dopaminergic and serotonergic transmission in the central and peripheral nervous system and it indirectly affects norepinephrine (noradrenaline) synthesis by way of inhibiting dopamine synthesis. Methyldopa acts on alpha-2 adrenergic receptors, which are found on the pre synaptic nerve terminal. This inhibits the release of norepinephrine from the presynaptic neuron. The S-enantiomer of methyldopa is a competitive inhibitor of the enzyme aromatic L-amino acid decarboxylase (LAAD), which converts L-DOPA into dopamine. L-DOPA can cross the blood–brain barrier and thus methyldopa may have similar effects. LAAD converts it into alpha-methyldopamine, a false precursor to norepinephrine, which in turn reduces synthesis of norepinephrine in the vesicles. Dopamine beta hydroxylase (DBH) converts alpha-methyldopamine into alpha-methylnorepinephrine, which is an agonist of the presynaptic α2-adrenergic receptor causing inhibition of neurotransmitter release. Methyldopa has been found to be a monoamine depleting agent.
Sources: en.wikipedia.org
==== Ukraine ==== During the Biden administration and the start of the Russian invasion of Ukraine, there were initially significant tensions regarding India's ties with Russia. However, the second Trump administration is anticipated to seek a quick end to the conflict, likely reducing India's distance from the United States on European security issues.
=== Carbon dioxide transport === CO2 is carried in blood in three different ways. (The exact percentages vary depending whether it is arterial or venous blood). Most of it (about 70%) is converted to bicarbonate ions HCO−3 by the enzyme carbonic anhydrase in the red blood cells by the reaction CO2 + H2O → H2CO3 → H+ + HCO−3; about 7% is dissolved in the plasma; and about 23% is bound to hemoglobin as carbamino compounds. Hemoglobin, the main oxygen-carrying molecule in red blood cells, carries both oxygen and carbon dioxide. However, the CO2 bound to hemoglobin does not bind to the same site as oxygen. Instead, it combines with the N-terminal groups on the four globin chains. However, because of allosteric effects on the hemoglobin molecule, the binding of CO2 decreases the amount of oxygen that is bound for a given partial pressure of oxygen. The decreased binding to carbon dioxide in the blood due to increased oxygen levels is known as the Haldane effect, and is important in the transport of carbon dioxide from the tissues to the lungs. A rise in the partial pressure of CO2 or a lower pH will cause offloading of oxygen from hemoglobin, which is known as the Bohr effect.
=== Initial hospital management === The clinician must protect the patient against hypotension, kidney failure, acidosis, hyperkalemia and hypocalcemia. Admission to an intensive care unit, preferably one experienced in trauma medicine, may be appropriate; even well-seeming patients need observation. Open wounds should be treated as surgically appropriate, with debridement, antibiotics and tetanus toxoid; ice should be applied to injured areas. Breathing and circulation must be checked and the patient should be given oxygen if eligible. Oral or intravenous fluids must be given depending on the measured amounts of electrolytes, arterial blood gases, and muscle enzymes. Intravenous hydration of up to 1.5 L/h should continue to prevent hypotension. A urinary output of at least 300 mL/h should be maintained with IV fluids and mannitol, and hemodialysis considered if an increase in urine is not achieved. Intravenous sodium bicarbonate should be used to keep the urine pH at 6.5 or greater, to prevent myoglobin and uric acid deposition in kidneys. To prevent hyperkalemia/hypocalcemia, consider the following adult doses:
Sources: en.wikipedia.org
The US government responded by saying the Rhodesian mission and its staff had no official diplomatic status and violated no US laws. Portugal pursued a middle path with Rhodesia. While not officially recognising Rhodesia under Ian Smith, the government of António Salazar did permit Rhodesia to establish a representative mission in Lisbon, and permitted Rhodesian exports and imports through their province of Mozambique. The Portuguese government in power at that time, authoritarian and ardently anti-communist, gave active behind-the-scenes support in Rhodesia's fight against the guerrilla groups. South Africa, itself under international pressure as a white minority government, pursued a policy of détente with the black African states at the time. These states wanted South Africa to pressure Ian Smith to accept a faster transition to majority rule in Rhodesia, in return for pledges of non-interference in South Africa's internal affairs. Prime Minister John Vorster, believing majority rule in Rhodesia would lead to international acceptance for South Africa, used a number of tactics to pressure Smith. The South African government held up shipments of fuel and ammunition and pulled out friendly South African forces from Rhodesia. The combined loss of Mozambique and the loss of support from South Africa dealt critical blows to the Rhodesian government.
==== MeSH D12.776.575.750.500 – mitochondrial adp, atp translocases ==== MeSH D12.776.575.750.500.100 – adenine nucleotide translocator 1 MeSH D12.776.575.750.500.200 – adenine nucleotide translocator 2 MeSH D12.776.575.750.500.300 – adenine nucleotide translocator 3
In February 2025, US president Trump imposed a 10% tariff on Chinese imports, claiming the move as a way "to pressure China into taking action on fentanyl" but experts have expressed concern that these tariffs could reverse the progress made under the Biden administration and weaken the international cooperation necessary to combat global drug trafficking. India has also emerged as a source of fentanyl and fentanyl precursors, where Mexican cartels have already developed networks for the import of synthetic drugs. It is possible that fentanyl and precursor production may disperse to other countries, such as Nigeria, South Africa, Indonesia, Myanmar, and the Netherlands. In 2020, the Myanmar military and police confiscated 990 gallons of "methyl fentanyl" [sic], as well as precursors for the illicit synthesis of the drug. According to the United Nations Office on Drugs and Crime, the Shan State of Myanmar has been identified as a major source for fentanyl derivatives. In 2021, the agency reported a further drop in opium poppy cultivation in Burma, as the region's synthetic drug market continues to expand and diversify. According to the national archives and the Drug Enforcement Administration (DEA), direct fentanyl shipments from China have stopped since 2022. The majority of illicit fentanyl and analogues now entering the U.S. from Mexico are final products in the form of "tablets", and adulterated heroin from previously synthesized fentanyl.
== Medical uses == Vancomycin is indicated for the treatment of serious, life-threatening infections by Gram-positive bacteria of both aerobic and anaerobic types that are unresponsive to other antibiotics. The increasing emergence of vancomycin-resistant enterococci (VRE) has resulted in the development of guidelines for use by the Centers for Disease Control Hospital Infection Control Practices Advisory Committee. These guidelines restrict use of vancomycin to these indications:
Sources: en.wikipedia.org
SR9009 is a synthetic research compound that activates the REV-ERBα and REV-ERBβ nuclear receptors. It is not an approved drug and has no established human therapeutic use. Most published biological data come from cell and rodent studies.
No. SR9009 is frequently mislabeled as a SARM in online discussions, but it does not target androgen receptors. Its known mechanism involves REV-ERB nuclear receptors and circadian-metabolic gene regulation.
Human clinical data are very limited. There is no approved human use, and safety and efficacy in people are not established. Most evidence comes from preclinical models, so effects observed in animals may not apply to humans.
Its legal status depends on the country and intended use. It is not an approved medicine in major jurisdictions. In sport, it is prohibited by anti-doping rules.