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Radiosynthesis and in vivo evaluation of [11C]MP-10 as a PET probe for imaging PDE10A in rodent and non-human primate brain.

ABSTRACT: 2-((4-(1-[(11)C]Methyl-4-(pyridin-4-yl)-1H-pyrazol-3-yl)phenoxy)methyl)-quinoline (MP-10), a specific PDE10A inhibitor (IC(50)=0.18 nM with 100-fold selectivity over other PDEs), was radiosynthesized by alkylation of the desmethyl precursor with [(11)C]CH(3)I, ?45% yield, >92% radiochemical purity, >370 GBq/?mol specific activity at end of bombardment (EOB). Evaluation in Sprague-Dawley rats revealed that [(11)C]MP-10 had highest brain accumulation in the PDE10A enriched-striatum, the 30 min striatum: cerebellum ratio reached 6.55. MicroPET studies of [(11)C]MP-10 in monkeys displayed selective uptake in striatum. However, a radiolabeled metabolite capable of penetrating the blood-brain-barrier may limit the clinical utility of [(11)C]MP-10 as a PDE10A PET tracer.

SUBMITTER: Tu Z

PROVIDER: S-EPMC3056285 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Radiosynthesis and in vivo evaluation of [11C]MP-10 as a PET probe for imaging PDE10A in rodent and non-human primate brain.

Tu Zhude Z Fan Jinda J Li Shihong S Jones Lynne A LA Cui Jinquan J Padakanti Prashanth K PK Xu Jinbin J Zeng Dexing D Shoghi Kooresh I KI Perlmutter Joel S JS Mach Robert H RH

Bioorganic & medicinal chemistry 20110122 5

2-((4-(1-[(11)C]Methyl-4-(pyridin-4-yl)-1H-pyrazol-3-yl)phenoxy)methyl)-quinoline (MP-10), a specific PDE10A inhibitor (IC(50)=0.18 nM with 100-fold selectivity over other PDEs), was radiosynthesized by alkylation of the desmethyl precursor with [(11)C]CH(3)I, ∼45% yield, >92% radiochemical purity, >370 GBq/μmol specific activity at end of bombardment (EOB). Evaluation in Sprague-Dawley rats revealed that [(11)C]MP-10 had highest brain accumulation in the PDE10A enriched-striatum, the 30 min str ...[more]

PMID: 21315609

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