2024
PET imaging of M4 muscarinic acetylcholine receptors in rhesus macaques using [11C]MK-6884: Quantification with kinetic modeling and receptor occupancy by CVL-231 (emraclidine), a novel positive allosteric modulator
Belov V, Guehl N, Duvvuri S, Iredale P, Moon S, Dhaynaut M, Chakilam S, MacDonagh A, Rice P, Yokell D, Renger J, Fakhri G, Normandin M. PET imaging of M4 muscarinic acetylcholine receptors in rhesus macaques using [11C]MK-6884: Quantification with kinetic modeling and receptor occupancy by CVL-231 (emraclidine), a novel positive allosteric modulator. Cerebrovascular And Brain Metabolism Reviews 2024, 44: 1329-1342. PMID: 38477292, PMCID: PMC11342722, DOI: 10.1177/0271678x241238820.Peer-Reviewed Original ResearchConceptsPositive allosteric modulatorsReceptor occupancyNon-human primatesBinding potentialPositron emission tomographyMuscarinic acetylcholine receptorsAllosteric modulatorsNon-human primate brainM4 muscarinic acetylcholine receptorStriatal hyperdopaminergiaAcetylcholine receptorsBrain regionsCaudate nucleusTotal volume of distributionDose-dependent blockReference regionVolume of distributionPositron emission tomography imagingEmission tomographyReceptor levelsFunction of dosePET scansClinical trialsBlood-basedRhesus macaques
2023
Tau Positron Emission Tomography and Neurocognitive Function Among Former Professional American-Style Football Players
Dhaynaut M, Grashow R, Normandin M, Wu O, Marengi D, Terry D, Sanchez J, Weisskopf M, Speizer F, Taylor H, Guehl N, Seshadri S, Beiser A, Daneshvar D, Johnson K, Iverson G, Zafonte R, Fakhri G, Baggish A. Tau Positron Emission Tomography and Neurocognitive Function Among Former Professional American-Style Football Players. Journal Of Neurotrauma 2023, 40: 1614-1624. PMID: 37282582, PMCID: PMC10458363, DOI: 10.1089/neu.2022.0454.Peer-Reviewed Original ResearchConceptsPositron emission tomographyDistribution volume ratioNeuropsychological testsNeurocognitive functionStandardized uptake value ratioControl participantsMeasures of neurocognitive functionStructural magnetic resonance imagingMeasures of memoryDepressive symptom severityMale control participantsEmission tomographyCerebellar gray matterNeuropsychological measuresTau positron emission tomographyExecutive functionSymptom severityBrain regionsEntorhinal cortexRepetitive head impactsP-tauReference regionFormer playersRepetitive head impact exposureMale controls
2022
Radiochemical Synthesis and Evaluation of 3‑[11C]Methyl-4-aminopyridine in Rodents and Nonhuman Primates for Imaging Potassium Channels in the CNS
Sun Y, Guehl N, Zhou Y, Takahashi K, Belov V, Dhaynaut M, Moon S, Fakhri G, Normandin M, Brugarolas P. Radiochemical Synthesis and Evaluation of 3‑[11C]Methyl-4-aminopyridine in Rodents and Nonhuman Primates for Imaging Potassium Channels in the CNS. ACS Chemical Neuroscience 2022, 13: 3342-3351. PMID: 36417797, PMCID: PMC9732819, DOI: 10.1021/acschemneuro.2c00364.Peer-Reviewed Original ResearchConceptsRegional brain time-activity curvesBrain time-activity curvesOne-tissue compartment modelBlood-brain barrierConsistent with <i>inNonhuman primatesTime-activity curvesPositron emission tomographySpinal cord injuryDemyelinated neuronsNeurological symptomsPotassium channelsNeuronal conductionBrain uptakeEmission tomographyStille cross-couplingMultiple sclerosisCord injurySlow kineticsBrain permeabilityTraumatic brainMyelin sheathStronger binding affinityNeuronsBrainPET imaging studies to investigate functional expression of mGluR2 using [11C]mG2P001
Yuan G, Dhaynaut M, Guehl N, Neelamegam R, Moon S, Qu X, Poutiainen P, Afshar S, Fakhri G, Normandin M, Brownell A. PET imaging studies to investigate functional expression of mGluR2 using [11C]mG2P001. Cerebrovascular And Brain Metabolism Reviews 2022, 43: 296-308. PMID: 36172629, PMCID: PMC9903221, DOI: 10.1177/0271678x221130387.Peer-Reviewed Original ResearchConceptsPositive allosteric modulatorsPositron emission tomographyNon-human primatesMGluR2 positive allosteric modulatorPositron emission tomography imagingPositive allosteric modulator of mGluR2Metabotropic glutamate receptor 2Positron emission tomography imaging studiesExpression of mGluR2Glutamate receptor 2MGluR2 functionPsychiatric disordersMGluR2 expressionTissue glutamate concentrationMGluR2Expressing mGluR2Allosteric modulatorsRat brainTransfected CHO cellsReceptor 2Glutamate concentrationEmission tomographyImaging studiesPharmacological effectsImaging ligandsSynthesis and Characterization of 5‑(2-Fluoro-4‑[11C]methoxyphenyl)-2,2-dimethyl-3,4-dihydro‑2H‑pyrano[2,3‑b]pyridine-7-carboxamide as a PET Imaging Ligand for Metabotropic Glutamate Receptor 2
Yuan G, Dhaynaut M, Lan Y, Guehl N, Huynh D, Iyengar S, Afshar S, Jain M, Pickett J, Kang H, Wang H, Moon S, Ondrechen M, Wang C, Shoup T, Fakhri G, Normandin M, Brownell A. Synthesis and Characterization of 5‑(2-Fluoro-4‑[11C]methoxyphenyl)-2,2-dimethyl-3,4-dihydro‑2H‑pyrano[2,3‑b]pyridine-7-carboxamide as a PET Imaging Ligand for Metabotropic Glutamate Receptor 2. Journal Of Medicinal Chemistry 2022, 65: 2593-2609. PMID: 35089713, PMCID: PMC9434702, DOI: 10.1021/acs.jmedchem.1c02004.Peer-Reviewed Original ResearchConceptsNegative allosteric modulatorsMetabotropic glutamate receptor 2Positron emission tomographyGlutamate receptor 2MGluR2 functionNeuropsychiatric disordersDrug effectsBrain heterogeneityReceptor 2Allosteric modulatorsMGluR2Nonhuman primatesBrain imagingPositron emission tomography imagingPositron emission tomography imaging ligandsHigh molar activityEmission tomographyExcellent radiochemical purityImaging ligandsBlocking agentsPET imagingMolar activityTherapeutic targetMetabotropicDisorders