Iomazenil Explained

Iomazenil (also known as Ro16-0154, INN, USAN; benzodine) is an antagonist and partial inverse agonist of benzodiazepine and a potential treatment for alcohol use disorder. The compound was introduced in 1989 by pharmaceutical company Hoffmann-La Roche as an Iodine-123-labelled SPECT tracer for imaging benzodiazepine receptors (GABA_A receptors) in the brain. Iomazenil is an analogue of flumazenil (Ro15-1788).^[1]

Use in brain research

¹²³I-labelled iomazenil can be used to image epileptic seizure foci as an alternative to ¹⁸F-fludeoxyglucose PET imaging.^{[2] [3]}

The effect of iomazenil of reducing levels of GABA in the brain was used by researchers to exacerbate symptoms in patients with schizophrenia in a laboratory study, supporting the theory that a GABA deficiency underlies that disease.^[4]

Alcohol treatment

Researchers at Yale University and Veterans Affairs Connecticut Healthcare System have been testing iomazenil as a potential treatment for drunkenness due to its ability to bind alcohol receptors in the brain.^[5]

See also

• GABA_A receptor negative allosteric modulator
• GABA_A receptor § Ligands

External links

• Book: [123I]Iomazenil . . US National Center for Biotechnology Information (NCBI) . 2004 . 20641688 . The MICAD Research Team .

Notes and References

1. Höll K, Deisenhammer E, Dauth J, Carmann H, Schubiger PA . Imaging benzodiazepine receptors in the human brain by single photon emission computed tomography (SPECT) . International Journal of Radiation Applications and Instrumentation. Part B, Nuclear Medicine and Biology . 16 . 8 . 759–63 . 1989 . 2559905 . 10.1016/0883-2897(89)90158-x .
2. Kung HF, Kung MP, Choi SR . Radiopharmaceuticals for single-photon emission computed tomography brain imaging . Seminars in Nuclear Medicine . 33 . 1 . 2–13 . January 2003 . 12605353 . 10.1053/snuc.2003.127296 .
3. Goethals I, Van de Wiele C, Boon P, Dierckx R . Is central benzodiazepine receptor imaging useful for the identification of epileptogenic foci in localization-related epilepsies? . European Journal of Nuclear Medicine and Molecular Imaging . 30 . 2 . 325–8 . February 2003 . 12552355 . 10.1007/s00259-002-1083-z . 27969321 .
4. Ahn K, Gil R, Seibyl J, Sewell RA, D'Souza DC . Probing GABA receptor function in schizophrenia with iomazenil . Neuropsychopharmacology . 36 . 3 . 677–83 . February 2011 . 21068719 . 3055690 . 10.1038/npp.2010.198 . Nature Publishing Group .
5. News: Tests begin on new drink-busting drug. Dobson R, Owen J . 13 May 2012. Independent on Sunday. 20 May 2012.