title: Evaluation of radioiodinated iodoclorgyline as a SPECT radiopharmaceutical for MAO-A in the brain.
abstract: An in vivo estimation of the newly synthesized MAO-A specific inhibitor, [125I]-labeled N-[3(2,4-dichloro-6-iodophenoxy)propyl]-N-methyl-2- propynylamine ([125I]-iodoclorgyline), was performed. Retention of the radioactivity of this radioligand was observed in the brain from 1 h post-injection. Pretreatments with clorgyline and l-deprenyl showed selective binding of [125I]-iodoclorgyline to MAO-A in the brain at 24 h post-injection. Moreover, a good correlation (r = 0.907) between the uptake of [125I]-iodoclorgyline and MAO-A enzyme activity in the cortex was observed in the pretreatment study with several doses of clorgyline. Although improvement to increase the brain/blood ratio is desirable because of slow blood clearance of the radioactivity, radioiodinated iodoclorgyline may serve as a useful SPECT radiopharmaceutical for quantitative analysis of MAO-A in the brain.
authors.affiliation: Department of Radiopharmaceutical Chemistry, Faculty of Pharmaceutical Sciences, Kyoto University, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Hirata
authors.forename: Y
authors.initials: Y
authors.lastname: Magata
authors.forename: Y
authors.initials: Y
authors.lastname: Ohmomo
authors.forename: H
authors.initials: H
authors.lastname: Saji
authors.forename: K
authors.initials: K
authors.lastname: Murakami
authors.forename: T
authors.initials: T
authors.lastname: Takagaki
authors.forename: N
authors.initials: N
authors.lastname: Yamamura
authors.forename: C
authors.initials: C
authors.lastname: Tanaka
authors.forename: J
authors.initials: J
authors.lastname: Konishi
authors.forename: A
authors.initials: A
authors.lastname: Yokoyama
mesh_terms: D000818:Animals; D001345:Autoradiography / Q000379:methods; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism; D003010:Clorgyline / Q000031:analogs & derivatives* / Q000378:metabolism / Q000493:pharmacokinetics / Q000494:pharmacology; D007457:Iodine Radioisotopes / Q000378:metabolism* / Q000493:pharmacokinetics; D007527:Isoenzymes / Q000032:analysis / Q000378:metabolism; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008928:Mitochondria / Q000378:metabolism; D008995:Monoamine Oxidase / Q000032:analysis / Q000378:metabolism*; D011869:Radioligand Assay / Q000379:methods; D012642:Selegiline / Q000494:pharmacology; D014018:Tissue Distribution; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: D007457:Iodine Radioisotopes; D007527:Isoenzymes; C074503:6-iodoclorgyline; D012642:Selegiline; D008995:Monoamine Oxidase; D003010:Clorgyline