Mefway (18F)

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Mefway (18F)
Mefway 18F skeletal.svg
Clinical data
Pregnancy
category
  • N/A
ATC code
  • none
Legal status
Legal status
  • Research compound
Identifiers
  • 4-[(18F)fluoromethyl]-N-{2-[4-(2-methoxyphenyl)piperazin-1-yl]ethyl}-N-(pyridin-2-yl)cyclohexane-1-carboxamide
CAS Number
PubChem CID
ChemSpider
UNII
CompTox Dashboard (EPA)
Chemical and physical data
Formula C26H35FN4O2
Molar mass 454.590 g·mol−1
3D model (JSmol)
  • COC1=CC=CC=C1N2CCN(CC2)CCN(C3=CC=CC=N3)C(=O)C4CCC(CC4)C[18F]
  • InChI=1S/C26H35FN4O2/c1-33-24-7-3-2-6-23(24)30-17-14-29(15-18-30)16-19-31(25-8-4-5-13-28-25)26(32)22-11-9-21(20-27)10-12-22/h2-8,13,21-22H,9-12,14-20H2,1H3/i27-1
  • Key:BQGLPDFQLBNUGU-FMLNDMEQSA-N

Mefway is a serotonin 5-HT1A receptor antagonist used in medical research, usually in the form of mefway (18F) as a positron emission tomography (PET) radiotracer. [1]

Contents

Chemistry

Mefway is closely related to the research compound WAY-100,635. The compound adds a fluoromethyl group to the cyclohexyl ring of WAY-100,635 and it is effectively prepared with automation module. [2] There are two isomers with regard to the cyclohexane ring, of which the trans conformation has the higher 5-HT1A specificity. [3]

Mefway cis-trans comparison.svg

Animal PET studies

In one study the uptake and retention of mefway (18F) was found to be similar to that found for 11C-WAY-100,635. Head-to-head comparison of mefway (18F) and 11C-WAY-100,635 have been evaluated. Since 11C-WAY-100,635 is the current 'gold standard' and difficult to synthesize, a suitable fluorine-18 replacement as in mefway is highly desired. [4] In addition, mefway (18F) showed comparable brain uptake and the target-to-reference ratios compared to fcway(18F) [5]

The ability to separately measure dissociation constant, KD and receptor density Bmax has been shown to be of potential value rather than simply comparing binding potential, BPND. Multiple injection mefway PET experiments can be used for the in-vivo measurement of 5-HT1A receptor density. [6]

Imaging studies of mefway on in vivo and ex vivo rat brains indicate that the substance binds to the known 5-HT1A receptor regions including the dorsal raphe. These findings support that the dorsal raphe is measurable in rat PET studies. [7] Mefway (18F) undergoes in vivo defluorination in rodent brain and this phenomenon was effectively suppressed by cytochrome P450 inhibitor (i.e. fluconazole). [8] Animal models of Parkinson's disease and the acute physical stress model exhibited significant decrement of binding potential in the hippocampus [9] [10]

Human PET studies

First-in-human studies have shown in vivo stability of mefway (18F) and its localization to 5-HT1A receptor-rich regions in the human brain, including the raphe nucleus. [11] Mefway (18F) is highly selective for the human serotonin 5-HT1A receptor and may therefore may be used to quantify serotonin 5-HT1A receptor distribution in brain regions for the study of various central nervous system disorders. [12]

Related Research Articles

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The 5-HT2A receptor is a subtype of the 5-HT2 receptor that belongs to the serotonin receptor family and is a G protein-coupled receptor (GPCR). The 5-HT2A receptor is a cell surface receptor, but has several intracellular locations. 5-HT is short for 5-hydroxy-tryptamine or serotonin. This is the main excitatory receptor subtype among the GPCRs for serotonin, although 5-HT2A may also have an inhibitory effect on certain areas such as the visual cortex and the orbitofrontal cortex. This receptor was first noted for its importance as a target of serotonergic psychedelic drugs such as LSD and psilocybin mushrooms. Later it came back to prominence because it was also found to be mediating, at least partly, the action of many antipsychotic drugs, especially the atypical ones.

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References

  1. Saigal N, Pichika R, Easwaramoorthy B, Collins D, Christian BT, Shi B, et al. (October 2006). "Synthesis and biologic evaluation of a novel serotonin 5-HT1A receptor radioligand, 18F-labeled mefway, in rodents and imaging by PET in a nonhuman primate". Journal of Nuclear Medicine. 47 (10): 1697–706. PMID   17015907.
  2. Choi JY, Kim CH, Ryu YH, Seo YB, Truong P, Kim EJ, et al. (October 2013). "Optimization of the radiosynthesis of [(18) F]MEFWAY for imaging brain serotonin 1A receptors by using the GE TracerLab FXFN-Pro module". Journal of Labelled Compounds & Radiopharmaceuticals. 56 (12): 589–94. doi:10.1002/jlcr.3067. PMID   24285234.
  3. Wooten D, Hillmer A, Murali D, Barnhart T, Schneider ML, Mukherjee J, Christian BT (October 2011). "An in vivo comparison of cis- and trans-[18F]mefway in the nonhuman primate". Nuclear Medicine and Biology. 38 (7): 925–32. doi:10.1016/j.nucmedbio.2011.04.001. PMC   3190069 . PMID   21741252.
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