2020
Preliminary in vivo evidence of lower hippocampal synaptic density in cannabis use disorder
D’Souza D, Radhakrishnan R, Naganawa M, Ganesh S, Nabulsi N, Najafzadeh S, Ropchan J, Ranganathan M, Cortes-Briones J, Huang Y, Carson RE, Skosnik P. Preliminary in vivo evidence of lower hippocampal synaptic density in cannabis use disorder. Molecular Psychiatry 2020, 26: 3192-3200. PMID: 32973170, DOI: 10.1038/s41380-020-00891-4.Peer-Reviewed Original ResearchConceptsHippocampal synaptic densityCannabis use disorderHealthy controlsSynaptic densityPositron emission tomographyUse disordersDSM-5 cannabis use disorderVivo evidenceAdministration of cannabinoidsHippocampal synaptic integrityVerbal memory taskSynaptic vesicle glycoprotein 2AHuman cannabis usersEffects of cannabisWarrants further studyPlasma input functionMemory taskCentrum semiovaleAdult rodentsOne-tissue compartment modelSynaptic integrityHippocampal functionCannabis misuseArterial samplingEmission tomography
2019
In vivo 5-HT6 and 5-HT2A receptor availability in antipsychotic treated schizophrenia patients vs. unmedicated healthy humans measured with [11C]GSK215083 PET
Radhakrishnan R, Matuskey D, Nabulsi N, Gaiser E, Gallezot JD, Henry S, Planeta B, Lin SF, Ropchan J, Huang Y, Carson RE, D'Souza DC. In vivo 5-HT6 and 5-HT2A receptor availability in antipsychotic treated schizophrenia patients vs. unmedicated healthy humans measured with [11C]GSK215083 PET. Psychiatry Research Neuroimaging 2019, 295: 111007. PMID: 31760336, DOI: 10.1016/j.pscychresns.2019.111007.Peer-Reviewed Original ResearchConceptsHealthy male controlsPositron emission tomographyMultilinear analysis 1Antipsychotic treatmentLower BPFrontal cortexReceptor availabilityAge-matched healthy male controlsDifferent second-generation antipsychoticsSteady-state troughPeak serum levelsSecond-generation antipsychoticsPotential therapeutic targetMale patientsSerum levelsHealthy humansTherapeutic targetSchizophrenia patientsTime-activity curvesMale controlsCognitive impairmentEmission tomographyVentral striatumPatientsSchizophrenia
2018
Dose-Related Target Occupancy and Effects on Circuitry, Behavior, and Neuroplasticity of the Glycine Transporter-1 Inhibitor PF-03463275 in Healthy and Schizophrenia Subjects
D’Souza D, Carson RE, Driesen N, Johannesen J, Ranganathan M, Krystal JH, Ahn K, Bielen K, Carbuto M, Deaso E, D’Souza D, Ranganathan M, Naganawa M, Ranganathan M, D’Souza D, Nabulsi N, Zheng M, Lin S, Huang Y, Carson R, Driesen N, Ahn K, Morgan P, Suckow R, He G, McCarthy G, Krystal J, Johannesen J, Kenney J, Gelernter J, Gueorguieva R, Pittman B. Dose-Related Target Occupancy and Effects on Circuitry, Behavior, and Neuroplasticity of the Glycine Transporter-1 Inhibitor PF-03463275 in Healthy and Schizophrenia Subjects. Biological Psychiatry 2018, 84: 413-421. PMID: 29499855, PMCID: PMC6068006, DOI: 10.1016/j.biopsych.2017.12.019.Peer-Reviewed Original ResearchMeSH KeywordsAdultAzabicyclo CompoundsBrainCognitive DysfunctionDose-Response Relationship, DrugDouble-Blind MethodFemaleGlycine Plasma Membrane Transport ProteinsHumansImidazolesKetamineLong-Term PotentiationMagnetic Resonance ImagingMaleMemory, Short-TermMiddle AgedPositron-Emission TomographySchizophreniaYoung AdultConceptsHealthy control subjectsLong-term potentiationSchizophrenia patientsControl subjectsCognitive impairmentClinical trialsGlyT1 occupancyN-methyl-D-aspartate receptor functionGlycine transporter-1 inhibitorKetamine-induced disruptionKetamine-induced effectsFunctional magnetic resonance imagingMagnetic resonance imagingPositron emission tomographyMemory-related activationF-MKSubstudy 1Schizophrenia subjectsResonance imagingReceptor functionCortical regionsEmission tomographyTarget engagementPotentiationSchizophrenia
2015
Reduced Brain Cannabinoid Receptor Availability in Schizophrenia
Ranganathan M, Cortes-Briones J, Radhakrishnan R, Thurnauer H, Planeta B, Skosnik P, Gao H, Labaree D, Neumeister A, Pittman B, Surti T, Huang Y, Carson RE, D’Souza D. Reduced Brain Cannabinoid Receptor Availability in Schizophrenia. Biological Psychiatry 2015, 79: 997-1005. PMID: 26432420, PMCID: PMC4884543, DOI: 10.1016/j.biopsych.2015.08.021.Peer-Reviewed Original ResearchConceptsHealthy control subjectsSCZ subjectsCB1R availabilityECB systemMale healthy control subjectsBody mass indexAge-matched male healthy control subjectsPathophysiology of schizophreniaPositron emission tomographyPosterior cingulate cortexPresence of abnormalitiesMass indexControl subjectsEndocannabinoid systemTobacco useReceptor availabilityCingulate cortexEmission tomography dataBrain regionsEmission tomographySelective radiotracerVivo measuresRegional volumesSchizophreniaPositron emission tomography data
1997
Imaging D2 Receptor Occupancy by Endogenous Dopamine in Humans
Laruelle M, D’Souza C, Baldwin R, Abi-Dargham A, Kanes S, Fingado C, Seibyl J, Zoghbi S, Bowers M, Jatlow P, Charney D, Innis R. Imaging D2 Receptor Occupancy by Endogenous Dopamine in Humans. Neuropsychopharmacology 1997, 17: 162-174. PMID: 9272483, DOI: 10.1016/s0893-133x(97)00043-2.Peer-Reviewed Original ResearchMeSH KeywordsAdultAffectAlpha-MethyltyrosineAnimalsBenzamidesBrainDopamineEnzyme InhibitorsHomovanillic AcidHumansIodine RadioisotopesMaleMethoxyhydroxyphenylglycolParkinson Disease, SecondaryPyrrolidinesRatsRats, Sprague-DawleyReceptors, Dopamine D2Tomography, Emission-Computed, Single-PhotonTyrosine 3-MonooxygenaseConceptsAcute dopamine depletionSynaptic dopamine concentrationsEndogenous dopamineDopamine depletionPositron emission tomographyD2 receptorsTyrosine hydroxylase inhibitor alpha-methylDopamine concentrationsD2 receptor imagingD2 receptor upregulationD2 receptor occupancySingle photon emissionPara-tyrosineReceptor upregulationReceptor imagingAlpha-methylReceptor occupancyEmission tomographyDopaminePhoton emissionHuman brainReceptorsTomographyRodentsVivo measurements