2020
Neuroimaging of Obsessive-Compulsive Disorder: Insights into Serotonergic Mechanisms
Lissemore J, Booij L, Leyton M, Gravel P, Sookman D, Nordahl T, Benkelfat C. Neuroimaging of Obsessive-Compulsive Disorder: Insights into Serotonergic Mechanisms. 2020, 457-478. DOI: 10.1007/978-3-030-57231-0_13.Peer-Reviewed Original ResearchSelective serotonin reuptake inhibitorsObsessive-compulsive disorderSerotonin synthesis capacityPositron emission tomographyHealthy controlsPET studiesOCD patientsSerotonin reuptake inhibitorsMost PET studiesBorderline personality disorderCognitive behavior therapySymptom onsetSerotonergic mechanismsClinical benefitSerotonergic toneSerotonergic alterationsSynthesis capacityEmission tomographySuicide attemptsSerotonin transporterPersonality disorderBehavior therapyGroup differencesDisordersPatientsDopaminergic Plasticity in the Bilateral Hippocampus Following Threat Reversal in Humans
Lissemore J, Nagano-Saito A, Smart K, Gravel P, Leyton M, Benkelfat C. Dopaminergic Plasticity in the Bilateral Hippocampus Following Threat Reversal in Humans. Scientific Reports 2020, 10: 7627. PMID: 32376865, PMCID: PMC7203150, DOI: 10.1038/s41598-020-63977-7.Peer-Reviewed Original ResearchConceptsPositron emission tomographyBilateral anterior hippocampusThreat reversalDopamine D2/3 receptor availabilityGreater dopamine releaseD2/3 receptor availabilityStress-related disordersClear clinical relevanceDopaminergic plasticityDopaminergic neurotransmissionHigh-resolution positron emission tomographyBilateral hippocampusDopamine releaseHealthy volunteersNeurochemical mechanismsHealthy humansPET scansClinical relevanceReceptor availabilityModerate evidenceAnterior hippocampusEmission tomographyFirst preliminary evidenceHippocampusDiminished ability
2014
Brain serotonin synthesis in MDMA (ecstasy) polydrug users: an alpha‐[11C]methyl‐l‐tryptophan study
Booij L, Soucy J, Young S, Regoli M, Gravel P, Diksic M, Leyton M, Pihl R, Benkelfat C. Brain serotonin synthesis in MDMA (ecstasy) polydrug users: an alpha‐[11C]methyl‐l‐tryptophan study. Journal Of Neurochemistry 2014, 131: 634-644. PMID: 25041501, DOI: 10.1111/jnc.12826.Peer-Reviewed Original ResearchConceptsMDMA polydrug usersMDMA usePolydrug usersLong-term neurotoxic effectsBrain serotonin synthesisSerotonin synthesis capacityDistal brain regionsNeurotoxicity of MDMAPositron emission tomographySynthesis capacityTracer alphaSerotonin synthesisNeurotoxic effectsPre-frontal regionsTemporal areaBrain regionsEmission tomographyCompensatory mechanismsTryptophan studiesParietal regionsMethylenedioxymethamphetamine (MDMA) useLonger durationBrainstemMDMA usersOCD: Serotonergic Mechanisms
Lissemore J, Leyton M, Gravel P, Sookman D, Nordahl T, Benkelfat C. OCD: Serotonergic Mechanisms. 2014, 433-450. DOI: 10.1007/978-3-642-40384-2_17.Peer-Reviewed Original ResearchSelective serotonin reuptake inhibitorsCognitive behavioral therapyObsessive-compulsive disorderPositron emission tomographySerotonergic mechanismsSerotonin reuptake inhibitorsSerotonin synthesis capacitySymptomatic improvementSymptom improvementCortico-striatoHealthy controlsSerotonin synthesisThalamic loopNeurobiological effectsEmission tomographyBrain circuitsBehavioral therapyNeurotransmitter serotoninBehavioral interventionsOCD patientsOCD pathologyRecent studiesSynthesis capacityTreatmentPatients
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 studies
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 sample
2008
MicroPET imaging of 5-HT1A receptors in rat brain: a test–retest [18F]MPPF study
Aznavour N, Benkelfat C, Gravel P, Aliaga A, Rosa-Neto P, Bedell B, Zimmer L, Descarries L. MicroPET imaging of 5-HT1A receptors in rat brain: a test–retest [18F]MPPF study. European Journal Of Nuclear Medicine And Molecular Imaging 2008, 36: 53. PMID: 18704404, DOI: 10.1007/s00259-008-0891-1.Peer-Reviewed Original ResearchConceptsPositron emission tomographyRaphe nucleusIsoflurane-anaesthetised ratsParaventricular hypothalamic nucleusMedial prefrontal cortexTest-retest variabilityNon-human primatesSimplified reference tissue modelReference tissue modelHypothalamic nucleiRaphe obscurusMagnetic resonance imaging dataBasolateral amygdaloidRat brainLarge brain regionsParaventricular hypothalamicBrain regionsEmission tomographyReceptor functionPrefrontal cortexMicroPET imagingBrain imagingRatsPotential of serotoninReceptors
2007
In vivo measurements of brain trapping of C-labelled alpha-methyl-L-tryptophan during acute changes in mood states.
Perreau-Linck E, Beauregard M, Gravel P, Paquette V, Soucy J, Diksic M, Benkelfat C. In vivo measurements of brain trapping of C-labelled alpha-methyl-L-tryptophan during acute changes in mood states. Journal Of Psychiatry And Neuroscience 2007, 32: 430-4. PMID: 18043767, PMCID: PMC2077345.Peer-Reviewed Original ResearchConceptsPositron emission tomographyBrain trappingEmotional statesRight anterior cingulate cortexNeutral emotional stateNeurobiology of emotionAnterior cingulate cortexWhole-brain analysisSubjects repeated-measures designState-related changesAcute changesL-tryptophanAutobiographical memoryRepeated-measures designHealthy peopleCingulate cortexBrain Imaging CenterEmission tomographyMood statesMcConnell Brain Imaging CentreBrain analysisNormal moodExperienced levelScan acquisitionSustained changes