If you have been reading about c-Met receptor 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 2026-07-10. Where a claim depends on a specific study, the study is described rather than over-claimed.
Dihexa is a synthetic peptide that has been examined in laboratory and animal research. Its design is based on angiotensin IV, a naturally occurring peptide fragment produced in the body. The short name dihexa appears in scientific papers and online discussions, while the full chemical name describes a modified peptide chain. It is not a vitamin, mineral, or plant-derived compound. Suppliers typically present it as a research chemical rather than an approved medicine.
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 is a synthetic compound studied in laboratory and animal models for effects on synaptic connectivity and cognitive performance. It is often described as a peptide analog because its structure incorporates amino acid residues linked to a hexanoic acid group. The molecule is not a naturally occurring human hormone or neurotransmitter. Its name appears in research literature and online discussions, but it has not been approved as a medicine by major regulatory agencies. Most information comes from preclinical experiments rather than controlled human trials.
The compound originated from work on angiotensin IV, a peptide fragment of the renin-angiotensin system. Researchers modified angiotensin IV-related structures to produce molecules with altered stability and activity. Dihexa emerged from that effort and was reported to promote dendritic spine growth in cultured neurons. Some studies link its effects to hepatocyte growth factor signaling and the c-Met receptor, while other work points to insulin-regulated aminopeptidase. The precise primary target remains a subject of investigation, and findings may depend on cell type, assay conditions, and species.
In animal research, dihexa has been administered through several routes, and reports describe improved performance on spatial learning and memory tasks in rodents. These results are frequently cited in discussions of nootropic compounds. However, species differences, small sample sizes, and varied testing protocols limit how far the findings can be generalized. No large randomized controlled trials in humans have established efficacy or long-term safety. Claims about human cognitive enhancement therefore remain speculative, and the compound is best described as an experimental laboratory substance rather than a proven therapeutic or supplement.
| 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. |
Dihexa is a synthetic peptide derived from angiotensin IV, a naturally occurring fragment of the renin-angiotensin system. Researchers modified the angiotensin IV structure to improve metabolic stability and central nervous system activity. It is frequently described as a hepatocyte growth factor mimetic because it can activate the c-Met receptor pathway in experimental systems. Its development reflects interest in small peptides that influence synaptic plasticity and cognitive processes. Most information comes from preclinical studies rather than controlled human trials.
The compound has been examined in animal models for effects on learning, memory, and synaptic connectivity. Some reports describe increased dendritic spine density and improved performance on certain behavioral tasks after administration in rodents. These findings are often cited in discussions of nootropic research peptides, but replication across independent laboratories remains limited. The absence of published phase 1 or phase 2 clinical trial data makes it difficult to assess safety, effective routes, or long-term outcomes in humans. Consequently, claims about cognitive benefits in people remain speculative.
Dihexa is a synthetic peptide studied in preclinical neuroscience. It is often described as an angiotensin IV analog or derivative. The compound also appears under research codes such as PNB-0408 and N-hexanoic-Tyr-Ile-(6)-aminohexanoic amide. It is not an approved drug, and it is not a conventional vitamin or nutrient. In many jurisdictions, material sold as dihexa is handled as a research chemical rather than a medicine or supplement. This classification affects how the material is labeled and distributed.
Chemically, dihexa is a short peptide-like molecule with nonstandard components. Its structure includes tyrosine and isoleucine residues linked to a hexanoic acid group and an aminohexanoic amide segment. This design distinguishes it from endogenous angiotensin IV, though the two are discussed together because of shared origins. Published summaries classify it as a small synthetic peptide with lipophilic features that may influence how it crosses biological barriers in experimental systems. Exact conformational details depend on the specific salt or free base form.
=== High blood pressure === A meta-analysis showed that L-arginine reduces blood pressure with pooled estimates of 5.4 mmHg for systolic blood pressure and 2.7 mmHg for diastolic blood pressure. Supplementation with l-arginine reduces diastolic blood pressure and lengthens pregnancy for women with gestational hypertension, including women with high blood pressure as part of pre-eclampsia. It did not lower systolic blood pressure or improve weight at birth.
== Transfer of pathogens by fomites == A fomite is any inanimate object (also called passive vector) that, when contaminated with or exposed to infectious agents (such as pathogenic bacteria, viruses or fungi), can transfer disease to a new host. Contamination can occur when one of these objects comes into contact with bodily secretions, like nasal fluid, vomit or feces from toilet plume. Many common objects can sustain a pathogen until a person comes in contact with the pathogen, increasing the chance of infection. The likely objects are different in a hospital environment than at home or in a workplace. Fomites such as splinters, barbed wire or farmyard surfaces, including soil, feeding troughs or barn beams, have been implicated as sources of virus.
A majority of Generation Z live in urban areas and are less inclined to change address than their predecessors. Similar to the Millennials, roughly two thirds of Generation Z come from households of married parents. By contrast, this living arrangement was essentially the norm for Generation X and the Baby Boomers, at 73% and 85%, respectively. As a demographic cohort, Generation Z is smaller than the Baby Boomers or their children, the Millennials. (See population pyramid.) According to the U.S. Census Bureau, Generation Z makes up about one quarter of the U.S. population. This demographic change could have social, cultural, and political implications for the decades ahead. Generation Z are usually the children of Generation X, and sometimes Millennials. Jason Dorsey, who works for the Center of Generational Kinetics, observed that Generation Z is not an extreme version of the Millennials but is rather different, and the differences can largely be attributed to parenting. Like parents from Generation X, members of Generation Z tend to be autonomous and pessimistic. They need validation less than the Millennials and typically become financially literate at an earlier age as many of their parents bore the full brunt of the Great Recession.
Sources: en.wikipedia.org
=== Tt dependence on ELP structure === The transition temperature of an ELP depends to a certain extent on the identity of the "X" residue found at the fourth position of the pentapeptide monomeric unit. Residues that are highly hydrophobic, such as leucine and phenylalanine, tend to decrease the transition temperature. On the other hand, residues that are highly hydrophilic, such as serine and glutamine, tend to increase the transition temperature. The presence of a potentially charged residue at the "X" position will determine how the ELP responds to varying pHs, with glutamic acid and aspartic acid raising the Tt at pH values in which the residues are deprotonated and lysine and arginine raising the Tt at pH values in which the residues are protonated. The pH needs to be compatible with the charged states of these amino acids in order to raise the Tt. Also higher molecular mass ELPs and higher concentrations of ELPs in solution make it much easier for the polymer to form aggregates, in effect lowering the experimental Tt.
). Another factor that impacts total CPU time needed by a simulation is the size of the integration timestep. This is the time length between evaluations of the potential. The timestep must be chosen small enough to avoid discretization errors (i.e., smaller than the period related to fastest vibrational frequency in the system). Typical timesteps for classical MD are on the order of 1 femtosecond (10−15 s). This value may be extended by using algorithms such as the SHAKE constraint algorithm, which fix the vibrations of the fastest atoms (e.g., hydrogens) into place. Multiple time scale methods have also been developed, which allow extended times between updates of slower long-range forces. For simulating molecules in a solvent, a choice should be made between an explicit and implicit solvent. Explicit solvent particles (such as the TIP3P, SPC/E and SPC-f water models) must be calculated expensively by the force field, while implicit solvents use a mean-field approach. Using an explicit solvent is computationally expensive, requiring inclusion of roughly ten times more particles in the simulation. But the granularity and viscosity of explicit solvent is essential to reproduce certain properties of the solute molecules. This is especially important to reproduce chemical kinetics. In all kinds of molecular dynamics simulations, the simulation box size must be large enough to avoid boundary condition artifacts.
== History == Phenylpiracetam was first described in the scientific literature by 1983. It was developed in 1983 as a medication for Soviet cosmonauts to treat the prolonged stresses of working in space. Phenylpiracetam was created at the Russian Academy of Sciences Institute of Biomedical Problems in an effort led by psychopharmacologist Valentina Ivanovna Akhapkina (Валентина Ивановна Ахапкина). Subsequently, it became available as a prescription drug in Russia. It was approved in 2003 for treatment of various conditions. Pilot-cosmonaut Aleksandr Serebrov described being issued and using phenylpiracetam, as well as it being included in the Soyuz spacecraft's standard emergency medical kit, during his 197-days working in space aboard the Mir space station. He reported "the drug acts as the equalizer of the whole organism, "tidying it up", completely excluding impulsiveness and irritability inevitable in the stressful conditions of space flight."
Sources: en.wikipedia.org
Xi's first marriage was to Ke Lingling, the daughter of Ke Hua, China's ambassador to the United Kingdom in the early 1980s. They divorced within a few years. The two were said to fight "almost every day," and after the divorce, Ke moved to the UK. In 1987, Xi married famed folk singer Peng Liyuan. Xi and Peng were introduced by friends as many Chinese couples were in the 1980s. Peng had gained fame in the 1980s and remained far better known in China than Xi until the latter emerged as a likely successor in the late 2000s. The couple frequently lived apart due largely to their separate professional lives. Peng has played a much more visible role as China's "first lady" compared to her predecessors; for example, Peng hosted U.S. First Lady Michelle Obama on her high-profile visit to China in March 2014. Xi and Peng have a daughter named Xi Mingze, who graduated from Harvard University in the spring of 2015. While at Harvard, she used a pseudonym and studied Psychology and English. Xi's family has a home in Jade Spring Hill, a garden and residential area in north-western Beijing run by the CMC. In June 2012, Bloomberg News reported that members of Xi's extended family including his sister Qi Qiaoqiao have substantial business interests, although there was no evidence he had intervened to assist them. The Bloomberg News website was blocked in mainland China in response to the article about his family's wealth and the sales of Bloomberg Terminals in China slowed, while access to the files of Qinchuan Dadi, which was Qi's investment vehicle, was shut down.
=== Hearing loss === Undiagnosed hearing loss in a child can have serious effects on many developmental areas, including language, social interactions, emotions, cognitive ability, academic performance and vocational skills, any combination of which can have negative impacts on the quality of life. The serious impacts of a late diagnosis, combined with the high incidence (estimated at 1 - 3 per 1000 live births, and as high as 4% for neonatal intensive care unit patients) have been the driving forces behind screening programs designed to identify infants with hearing loss as early as possible. Early identification allows these patients and their families to access the necessary resources to help them maximize their developmental outcomes.
=== Secondhand cannabis smoke === A 2022 study found that smoking cannabis using a bong can greatly increase background levels of fine particulate matter, a carcinogen, in an enclosed space such as a living room. After 15 minutes, mean levels of particulate matter were more than twice the Environmental Protection Agency hazardous air quality threshold, and after 140 minutes, the concentrations were four times greater than those generated by smoking tobacco using a cigarette or hookah. This suggests secondhand cannabis smoke from bongs may present a health risk to non-smokers.
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.
Dihexa is a synthetic peptide-like compound studied primarily in preclinical models. It is often classified as an angiotensin IV analog and has been investigated for effects on neuronal connectivity. It is not an approved drug or dietary supplement.