2013
Stress‐induced dopamine release in human medial prefrontal cortex—18F‐Fallypride/PET study in healthy volunteers
Nagano‐Saito A, Dagher A, Booij L, Gravel P, Welfeld K, Casey K, Leyton M, Benkelfat C. Stress‐induced dopamine release in human medial prefrontal cortex—18F‐Fallypride/PET study in healthy volunteers. Synapse 2013, 67: 821-830. PMID: 23939822, DOI: 10.1002/syn.21700.Peer-Reviewed Original ResearchConceptsStress-induced dopamine releaseDopamine releaseHeart ratePsychological stressorsMesocortical dopamine releaseHealthy young adultsSalivary cortisol levelsStress-induced increaseMedial prefrontal cortexPositron emission tomographyMesocortical dopamine systemStress-induced decreasePresent studyTissue compartmental modelMotor zoneHealthy volunteersRostal partDopamine systemCortisol levelsWhole brainBP NDDorsal partSeparate daysEmission tomographyPET studiesGrey matter density and GABAA binding potential show a positive linear relationship across cortical regions
Duncan N, Gravel P, Wiebking C, Reader A, Northoff G. Grey matter density and GABAA binding potential show a positive linear relationship across cortical regions. Neuroscience 2013, 235: 226-231. PMID: 23380503, DOI: 10.1016/j.neuroscience.2012.12.075.Peer-Reviewed Original Research
2012
External awareness and GABA—A multimodal imaging study combining fMRI and [18F]flumazenil‐PET
Wiebking C, Duncan N, Qin P, Hayes D, Lyttelton O, Gravel P, Verhaeghe J, Kostikov A, Schirrmacher R, Reader A, Bajbouj M, Northoff G. External awareness and GABA—A multimodal imaging study combining fMRI and [18F]flumazenil‐PET. Human Brain Mapping 2012, 35: 173-184. PMID: 22996793, PMCID: PMC6869063, DOI: 10.1002/hbm.22166.Peer-Reviewed Original ResearchConceptsNeuronal activity changesInhibitory neurotransmitter GABANegative BOLD responseFunctional magnetic resonance imaging paradigmCortical midline regionsSame healthy subjectsGABAA receptorsHealthy subjectsNeurotransmitter GABAPsychiatric disordersBiochemical mechanismsPET imagingExtrinsic systemMidline regionBOLD responseExternal awarenessNeuronal networksUnderlying neuronal networksImaging paradigmGABAActivity changesStimulus typeSame paradigmAwarenessPrecuneus
2011
Tryptophan hydroxylase2 gene polymorphisms predict brain serotonin synthesis in the orbitofrontal cortex in humans
Booij L, Turecki G, Leyton M, Gravel P, Lopez De Lara C, Diksic M, Benkelfat C. Tryptophan hydroxylase2 gene polymorphisms predict brain serotonin synthesis in the orbitofrontal cortex in humans. Molecular Psychiatry 2011, 17: 809-817. PMID: 21747395, DOI: 10.1038/mp.2011.79.Peer-Reviewed Original ResearchConceptsPositron emission tomographySerotonin synthesisTryptophan hydroxylase 2Orbitofrontal cortexRate-limiting enzymeSingle nucleotide polymorphismsL-tryptophan trappingRegional serotonin synthesisBrain serotonin synthesisTPH2 single nucleotide polymorphismsDose-effect relationshipBrain clearanceHealthy controlsGene polymorphismsAggressive behavioral phenotypeEmission tomographyHydroxylase 2TPH2 geneGenetic factorsCortexBehavioral phenotypesPolymorphismPatientsHumansLarge sampleBrain Regionalα-[11C]Methyl-L-Tryptophan Trapping in Medication-Free Patients With Obsessive-Compulsive Disorder
Berney A, Leyton M, Gravel P, Sibon I, Sookman D, Neto P, Diksic M, Nakai A, Pinard G, Todorov C, Okazawa H, Blier P, Nordahl T, Benkelfat C. Brain Regionalα-[11C]Methyl-L-Tryptophan Trapping in Medication-Free Patients With Obsessive-Compulsive Disorder. JAMA Psychiatry 2011, 68: 732-741. PMID: 21383250, PMCID: PMC3677917, DOI: 10.1001/archgenpsychiatry.2011.16.Peer-Reviewed Original ResearchConceptsL-tryptophan trappingObsessive-compulsive disorderMedication-free patientsHealthy controlsMcGill University Health CentreGlucose metabolic disturbancesAdults meeting criteriaMain outcome measuresUniversity Health CentrePositron emission tomographyDepartment of PsychiatryStatistical parametric mappingTemporal lobe activityMontreal Neurological InstituteSerotonergic componentReuptake inhibitorsSerotonin dysfunctionClinical efficacySerotonergic abnormalitiesMetabolic disturbancesPostsynaptic changesSymptomatic stateSerotonergic systemHealth centersOutcome measures