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Synthesis and in vitro autoradiographic evaluation of a novel high-affinity radioiodinated ligand for imaging brain cannabinoid subtype-1 receptors.

ABSTRACT: There is strong interest to study the involvement of brain cannabinoid subtype-1 (CB1) receptors in neuropsychiatric disorders with single photon emission computed tomography (SPECT) and a suitable radioligand. Here we report the synthesis of a novel high-affinity radioiodinated CB1 receptor ligand ([125I]8, [125I]1-(2-iodophenyl)-4-cyano-5-(4-methoxyphenyl)-N-(piperidin-1-yl)-1H-pyrazole-3-carboxylate, [125I]SD7015). By autoradiography in vitro, [125I]8 showed selective binding to CB1 receptors on human brain postmortem cryosections and now merits labeling with iodine-123 for further evaluation as a SPECT radioligand in non-human primate.

SUBMITTER: Donohue SR

PROVIDER: S-EPMC2792201 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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Synthesis and in vitro autoradiographic evaluation of a novel high-affinity radioiodinated ligand for imaging brain cannabinoid subtype-1 receptors.

Donohue Sean R SR Varnäs Katarina K Jia Zhisheng Z Gulyás Balázs B Pike Victor W VW Halldin Christer C

Bioorganic & medicinal chemistry letters 20090903 21

There is strong interest to study the involvement of brain cannabinoid subtype-1 (CB1) receptors in neuropsychiatric disorders with single photon emission computed tomography (SPECT) and a suitable radioligand. Here we report the synthesis of a novel high-affinity radioiodinated CB1 receptor ligand ([125I]8, [125I]1-(2-iodophenyl)-4-cyano-5-(4-methoxyphenyl)-N-(piperidin-1-yl)-1H-pyrazole-3-carboxylate, [125I]SD7015). By autoradiography in vitro, [125I]8 showed selective binding to CB1 receptors ...[more]

PMID: 19767206

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