CAS Registry Number 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.
Updated 2025-08-05. Numbers and descriptions here follow the published literature rather than marketing material.
The full name often given is N-hexanoic-Tyr-Ile-(6)-aminohexanoic amide. This name indicates a chain containing tyrosine, isoleucine, and a six-carbon amino acid derivative. Databases list a CAS Registry Number and a molecular formula for the compound. The peptide is small compared with proteins, and its structure allows it to be studied in cell cultures and animal models. Exact identity depends on the supplier's synthesis and purification process. Minor impurities can remain after synthesis.
Chemically, dihexa belongs to a broader group of angiotensin IV analogs. Researchers have modified the natural peptide to alter stability, binding, or distribution. Such changes can affect how the molecule behaves in experiments. The parent peptide angiotensin IV is involved in various physiological processes, but the modified analog is not identical to it. Public summaries sometimes blur the distinction between the natural fragment and the synthetic research compound. This distinction matters when interpreting study results.
Dihexa occupies an uncertain regulatory space in many countries. It is not generally listed as an approved therapeutic, and some jurisdictions may treat it as a research chemical, a compounded substance, or an unapproved new drug depending on claims and distribution. Importation can be restricted, and suppliers may require documentation that the material is for laboratory research only. Quality and labeling vary, so buyers should request analytical data, verify lot numbers, and understand local rules. These factors make sourcing and compliance part of the practical context around dihexa.
Lyophilized dihexa is typically stored as a dry powder at or below minus twenty degrees Celsius. Cooler temperatures slow degradation, and desiccant protection limits moisture uptake. Repeated temperature cycling can accelerate breakdown, so aliquoting before storage is common in laboratory practice. Solutions are generally less stable than dry powder and are often kept cold, protected from light, and used within a defined period. Specific stability data for dihexa are limited, and handling recommendations often follow general peptide guidelines rather than compound-specific studies.
Identity and purity are usually assessed with reverse-phase high-performance liquid chromatography and mass spectrometry. These methods can separate related impurities and confirm molecular mass, but they do not by themselves establish biological activity. Certificate of analysis documents may report purity as a percentage by area, yet the exact meaning can vary between laboratories. Independent testing can check for residual solvents, counterions, or microbial contamination when relevant. For research use, matching analytical records to a specific lot helps trace experimental variability.
| Property | Value | Notes |
|---|---|---|
| Common name | Dihexa | Shorthand used in research literature and supplier catalogs. |
| CAS Registry Number | 1401708-83-5 | Identifier assigned to the synthetic peptide. |
| Molecular formula | C27H44N4O5 | Reported formula; verify with a certificate of analysis. |
| Appearance | White to off-white powder | Typical form for lyophilized research peptides. |
| Typical storage | −20 °C or below, desiccated | Common condition for peptide stability. |
Development of dihexa followed from studies on angiotensin IV analogs and their effects on learning and memory. Researchers sought compounds with improved metabolic stability and brain penetration compared with natural peptides. In preclinical reports, dihexa was associated with changes in synaptic connectivity and performance on spatial tasks. These findings generated interest in its potential as a cognitive research tool. The work remains largely preclinical, and independent replication has been limited.
Regulatory and commercial contexts differ from clinical medicine. Dihexa is not approved as a drug by major agencies, and no published human trials establish its safety or efficacy. It is often sold as a research chemical labeled for laboratory use only. Suppliers may provide certificates of analysis, but purity and identity depend on the specific batch. Legal status varies by country and may treat such compounds as unapproved substances for human consumption.
Human safety data are sparse. No widely accepted dosing regimen, long-term safety profile, or clinical efficacy endpoint has been established. Published animal results can suggest directions for further study, but species differences and study design limit direct translation. Open questions include bioavailability, blood-brain barrier penetration, metabolism, and whether observed effects arise from a single target or multiple pathways. Replication across independent laboratories remains an important benchmark for evaluating the strength of preclinical claims.
Most published reports on dihexa come from cell cultures and animal models. Studies have examined markers of synapse formation, dendritic spine density, and performance on learning tasks in rodents. Proposed mechanisms center on hepatocyte growth factor and its c-Met receptor, with additional attention to angiotensin IV-related pathways. These findings are experimental and have not been confirmed as clinical benefits in humans. The literature often uses different tasks and endpoints, which complicates direct comparison across studies.
=== Nuclear technology === Cadmium is used in the control rods of nuclear reactors, acting as a very effective neutron poison to control neutron flux in nuclear fission. When cadmium rods are inserted in the core of a nuclear reactor, cadmium absorbs neutrons, preventing them from creating additional fission events, thus controlling the amount of reactivity. The pressurized water reactor designed by Westinghouse Electric Company uses an alloy consisting of 80% silver, 15% indium, and 5% cadmium.
In 1965, Alan Stillman opened the first TGI Fridays restaurant in Manhattan. He lived on 63rd Street between First and York Avenues, in a neighborhood with many airline stewardesses, fashion models, secretaries, and other young, single people on the East Side of Manhattan near the Queensboro Bridge. He hoped that opening a bar would help him meet women. Stillman's choices for socializing were non-public cocktail parties or guys' beer-drinking hangout bars that women usually would not visit; he recalled that "there was no public place for people between, say, twenty-three to thirty-seven years old, to meet." He sought to recreate the comfortable cocktail party atmosphere in public despite having no experience in the restaurant business. With US$5,000 of his own money and $5,000 borrowed from his mother, Stillman purchased a bar he often visited, The Good Tavern at the corner of 63rd Street and First Avenue, and renamed it TGI Fridays after the expression "Thank God it's Friday!" from his years at Bucknell University. The restaurant opened on March 15, 1965, serving standard American cuisine, bar food, and alcoholic beverages, and emphasized food quality and preparation. The exterior featured a red-and-white striped awning and blue paint; the Gay Nineties interior included Tiffany-style lamps, wooden floors, Bentwood chairs, and striped tablecloths; and the bar area added brass rails and stained glass.
(Full) agonists are able to activate the receptor and result in a strong biological response. The natural endogenous ligand with the greatest efficacy for a given receptor is by definition a full agonist (100% efficacy). Partial agonists do not activate receptors with maximal efficacy, even with maximal binding, causing partial responses compared to those of full agonists (efficacy between 0 and 100%). Antagonists bind to receptors but do not activate them. This results in a receptor blockade, inhibiting the binding of agonists and inverse agonists. Receptor antagonists can be competitive (or reversible), and compete with the agonist for the receptor, or they can be irreversible antagonists that form covalent bonds (or extremely high affinity non-covalent bonds) with the receptor and completely block it. The proton pump inhibitor omeprazole is an example of an irreversible antagonist. The effects of irreversible antagonism can only be reversed by synthesis of new receptors. Inverse agonists reduce the activity of receptors by inhibiting their constitutive activity (negative efficacy). Allosteric modulators: They do not bind to the agonist-binding site of the receptor but instead on specific allosteric binding sites, through which they modify the effect of the agonist. For example, benzodiazepines (BZDs) bind to the BZD site on the GABAA receptor and potentiate the effect of endogenous GABA. Note that the idea of receptor agonism and antagonism only refers to the interaction between receptors and ligands and not to their biological effects.
The first class of adenylyl cyclases occur in many bacteria including E. coli (as CyaA P00936 [unrelated to the Class II enzyme]). This was the first class of AC to be characterized. It was observed that E. coli deprived of glucose produce cAMP that serves as an internal signal to activate expression of genes for importing and metabolizing other sugars. cAMP exerts this effect by binding the transcription factor CRP, also known as CAP. Class I AC's are large cytosolic enzymes (~100 kDa) with a large regulatory domain (~50 kDa) that indirectly senses glucose levels. As of 2012, no crystal structure is available for class I AC. Some indirect structural information is available for this class. It is known that the N-terminal half is the catalytic portion, and that it requires two Mg2+ ions. S103, S113, D114, D116 and W118 are the five absolutely essential residues. The class I catalytic domain (Pfam PF12633) belongs to the same superfamily (Pfam CL0260) as the palm domain of DNA polymerase beta (Pfam PF18765). Aligning its sequence onto the structure onto a related archaeal CCA tRNA nucleotidyltransferase (PDB: 1R89) allows for assignment of the residues to specific functions: γ-phosphate binding, structural stabilization, DxD motif for metal ion binding, and finally ribose binding.
Technetium-99m (99mTc) is a metastable nuclear isomer of technetium-99 (itself an isotope of technetium), symbolized as 99mTc, that is used in tens of millions of medical diagnostic procedures annually, making it the most commonly used medical radioisotope in the world. Technetium-99m is used as a radioactive tracer and can be detected in the body by medical equipment (gamma cameras). It is well suited to the role, because it emits readily detectable gamma rays with a photon energy of 140.5 keV (within the range emitted by conventional X-ray diagnostic equipment) and its half-life is 6.0066 hours (meaning 93.7% of it decays to 99Tc in 24 hours). The relatively short physical half-life of the isotope and its biological half-life of 1 day (in terms of human activity and metabolism) allows for scanning procedures which collect data rapidly but keep total patient radiation exposure low. The same characteristics make the isotope unsuitable for therapeutic use because Technetium-99m emits penetrating gamma rays and decays quickly, so it cannot deliver a strong, localized dose to destroy diseased tissue. Technetium-99m was discovered as a product of cyclotron bombardment of molybdenum. This procedure produced molybdenum-99, a radionuclide with a longer half-life (2.75 days), which decays to 99mTc. This longer decay time allows for 99Mo to be shipped to medical facilities, where 99mTc is extracted from the sample as it is produced.
Sources: en.wikipedia.org
== Genomics == The gene is located on long arm of chromosome 11 (11q13) between base pairs 64,570,985 and 64,578,765. It has 10 exons and encodes a 610-amino acid protein. Over 1300 mutations have been reported to date (2010). The majority (>70%) of these are predicted to lead to truncated forms are scattered throughout the gene. Four - c.249_252delGTCT (deletion at codons 83-84), c.1546_1547insC (insertion at codon 516), c.1378C>T (Arg460Ter) and c.628_631delACAG (deletion at codons 210-211) have been reported to occur in 4.5%, 2.7%, 2.6% and 2.5% of families.
=== Biomedicine === Blood tests for lipase may be used to help investigate and diagnose acute pancreatitis and other disorders of the pancreas. Measured serum lipase values may vary depending on the method of analysis. In patients with exocrine pancreatic insufficiency, pancreatic enzyme replacement therapy (PERT) is used to replace the various enzymes that are produced by the pancreas the supplementation of pancreatic enzymes to treat. Enzyme mixtures used for PERT will include lipase, amylase, and protease.
The subarachnoid space is the space that normally exists between the arachnoid and the pia mater. It is filled with cerebrospinal fluid and continues down the spinal cord. Spaces are formed from openings at different points along the subarachnoid space; these are the subarachnoid cisterns, which are filled with cerebrospinal fluid. The dura mater is attached to the skull, whereas in the spinal cord, the dura mater is separated from the vertebrae by a space called the epidural space, which contains fat and blood vessels. The arachnoid is attached to the dura mater, while the pia mater is attached to the central nervous system tissue. If the dura mater and the arachnoid become separated due to injury or illness, the space between them is known as the subdural space. There is another potential space, the subpial space, between the pia mater and the glia limitans.
PHF8: PHD finger protein 8 belongs to the family of ferrous iron and 2-oxoglutarate dependent oxygenases, and is a histone lysine demethylase with selectivity for the di-and monomethyl states. FMR2: Fragile mental retardation 2 (FMR2: synonym AFF2), the protein belongs to the AFF family which currently has four members: AFF1/AF4, AFF2/FMR2, AFF3/LAF4 and AFF4/AF5q31. All AFF proteins are localized in the nucleus and have a role as transcriptional activators with a positive action on RNA elongation. AFF2/FMR2, AFF3/LAF4 and AFF4/AF5q31 localize in nuclear speckles (subnuclear structures considered to be storage/modification sites of pre-mRNA splicing factors) and are able to bind RNA with a high apparent affinity for the G-quadruplex structure. They appear to modulate alternative splicing via the interaction with the G-quadruplex RNA-forming structure. Slc6a8: Creatine transporter is a protein that is required for creatine to enter the cell. Creatine is essential for maintaining ATP levels in cells with a high energy demand. GSPT2 MAGED1 UBE2A OGT
Sources: en.wikipedia.org
=== X-ray and CT (computed tomography) === Chest radiography is usually the first test to detect interstitial lung diseases, but the chest radiograph can be normal in up to 10% of patients, especially early in the disease process. High-resolution CT of the chest is the preferred modality and differs from routine CT of the chest. Conventional (regular) CT chest examines 7–10 mm slices obtained at 10 mm intervals; high resolution CT examines 1–1.5 mm slices at 10 mm intervals using a high-spatial-frequency reconstruction algorithm. The HRCT therefore provides approximately 10 times more resolution than the conventional CT chest, allowing the HRCT to elicit details that cannot otherwise be visualized. Radiologic appearance alone, however, is not adequate and should be interpreted in the clinical context, keeping in mind the temporal profile of the disease process. Interstitial lung diseases can be classified according to radiologic patterns.
== External links == "Suzetrigine (Code C199115)". NCI Thesaurus. Clinical trial number NCT05661734 for "A Single-arm Study to Evaluate Safety and Effectiveness of VX-548 for Acute Pain" at ClinicalTrials.gov Clinical trial number NCT05558410 for "Evaluation of Efficacy and Safety of VX-548 for Acute Pain After an Abdominoplasty" at ClinicalTrials.gov
== Early life and education == Sur did his early schooling at the St. Joseph's Collegiate School, Allahabad. He received a Bachelor of Technology degree in electrical engineering from the Indian Institute of Technology in Kanpur (IIT Kanpur) in 1974, and Master of Science and PhD degrees in electrical engineering in 1975 and 1978, respectively, from Vanderbilt University in Nashville. After postdoctoral research at Stony Brook University, he was appointed to the faculty of Yale University School of Medicine in 1983.
===== Research ===== In 2016, a study from the University of Nottingham was published describing the first synthetic spider silk that is functionally identical to naturally spun spider silk. Using non-natural methionine analog L-azidohomoalanine (L-Aha) and genetically modified E-Coli cells, self-assembling proteins under the conditions needed to create the filament were produced. These conditions had been researched years earlier by J. Johansson and co-workers studying the production of spider silk proteins. The proteins used in the study are a miniaturized version of the silk monomers found in nature that behave the same way; because of the modifications, they were able to express functionalized regions of the protein 4RepCT, which is a self-assembling recombinant dragline silk protein, derived from the nursery-web spider along the axis of the filament.
Since the rescue mRNA would not affect phenotypic changes due to the Morpholino's off-target gene expression modulation, this return to wild-type phenotype is further evidence of Morpholino specificity. In some cases, ectopic expression of the rescue RNA makes recovery of the wild-type phenotype impossible. In embryos, Morpholinos can be tested in null mutants to check for unexpected RNA interactions, then used in a wild-type embryo to reveal the acute knockdown phenotype. The knockdown phenotype is often more extreme than the mutant phenotype; in the mutant, effects of losing the null gene can be concealed by genetic compensation. Because of their completely unnatural backbones, Morpholinos are not recognized by cellular proteins. Nucleases do not degrade Morpholinos, nor are they degraded in serum or in cells. Up to 18% of Morpholinos appear to induce nontarget-related phenotypes including cell death in the central nervous system and somite tissues of zebrafish embryos. Most of these effects are due to activation of p53-mediated apoptosis and can be suppressed by co-injection of an anti-p53 Morpholino along with the experimental Morpholino. Moreover, the p53-mediated apoptotic effect of a Morpholino knockdown has been phenocopied using another antisense structural type, showing the p53-mediated apoptosis to be a consequence of the loss of the targeted protein and not a consequence of the knockdown oligo type.
Sources: en.wikipedia.org
Dihexa is a synthetic peptide modeled on angiotensin IV. It is used in laboratory and animal research, not as an approved medicine. Human effects remain poorly characterized.
It is produced by chemical synthesis, not extracted from plants or animals. Its design is based on a naturally occurring peptide fragment. Suppliers sell it as a research chemical.
No, dihexa is a modified analog of angiotensin IV. The two share a structural relationship but differ in chemical details. Research on one does not automatically apply to the other.
The lyophilized powder is commonly kept at -20 °C or lower, protected from moisture and light. Solutions may require colder storage and should avoid repeated freeze-thaw cycles. General peptide stability practices apply.