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
2022
A multi-pronged investigation of option generation using depression, PET and modafinil
Ang Y, Cusin C, Petibon Y, Dillon D, Breiger M, Belleau E, Normandin M, Schroder H, Boyden S, Hayden E, Levine M, Jahan A, Meyer A, Kang M, Brunner D, Gelda S, Hooker J, Fakhri G, Fava M, Pizzagalli D. A multi-pronged investigation of option generation using depression, PET and modafinil. Brain 2022, 145: 1854-1865. PMID: 35150243, PMCID: PMC9166534, DOI: 10.1093/brain/awab429.Peer-Reviewed Original ResearchConceptsD2/D3 receptor availabilitySelf-generated optionsDepressive disorderDepressed individualsReceptor availabilityDopamine D2/D3 receptor availabilityNon-depressed adultsEffects of modafinilPutamen of patientsAssociated with uniquenessOption generationD2/D3 receptorsDopaminergic activityClinical depressionBinding potentialModafinilHealthy participantsPutamenPlacebo-controlledSamples of healthy peopleDouble-blindDisordersSelf-generationHealthy controlsDopamine
2017
Frontostriatal and Dopamine Markers of Individual Differences in Reinforcement Learning: A Multi-modal Investigation
Kaiser R, Treadway M, Wooten D, Kumar P, Goer F, Murray L, Beltzer M, Pechtel P, Whitton A, Cohen A, Alpert N, Fakhri G, Normandin M, Pizzagalli D. Frontostriatal and Dopamine Markers of Individual Differences in Reinforcement Learning: A Multi-modal Investigation. Cerebral Cortex 2017, 28: 4281-4290. PMID: 29121332, PMCID: PMC6454484, DOI: 10.1093/cercor/bhx281.Peer-Reviewed Original ResearchConceptsDA transporterRL behaviourVentral striatumDA clearanceFunctional connectivityBinding potentialLevel of neurocognitive functioningIncreased intrinsic functional connectivityMulti-modal neuroimaging studiesResting-state functional connectivityPhasic DA activityStriatal DA transporterIntrinsic functional connectivityReinforcement learning behaviorMulti-modal investigationsFrontostriatal circuitsFrontostriatal connectivityFrontostriatal regionsOrbitofrontal cortexDA activityNeuroimaging studiesOrbitofrontal regionsDopamine markersNeurocognitive functionDopamine
2005
Quantitative simultaneous 99mTc-ECD/123I-FP-CIT SPECT in Parkinson’s disease and multiple system atrophy
El Fakhri G, Habert M, Maksud P, Kas A, Malek Z, Kijewski M, Lacomblez L. Quantitative simultaneous 99mTc-ECD/123I-FP-CIT SPECT in Parkinson’s disease and multiple system atrophy. European Journal Of Nuclear Medicine And Molecular Imaging 2005, 33: 87-92. PMID: 16180033, DOI: 10.1007/s00259-005-1920-y.Peer-Reviewed Original ResearchConceptsMultiple system atrophyIdiopathic Parkinson's diseaseDopamine transporterDopamine transporter binding potentialNormal controlsVoxel-based statistical parametric mappingAsymmetry indexMultiple system atrophy patientsCompared to normal controlsCaudate nucleusDifferential diagnosis of idiopathic Parkinson’s diseaseDiagnosis of parkinsonian syndromesPatient-specific attenuationDiagnosis of idiopathic Parkinson's diseaseBinding potentialIdiopathic Parkinson's disease patientsDual-isotope SPECTVariable collimator responseParkinson's diseaseDifferential diagnosisDecreased perfusionStatistical parametric mappingPurposeThe purposeSystem atrophyParkinsonian syndromes