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Liaw YS, Augustine GJ. The claustrum and consciousness: An update. Int J Clin Health Psychol 2023; 23:100405. [PMID: 37701759 PMCID: PMC10493512 DOI: 10.1016/j.ijchp.2023.100405] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 08/10/2023] [Indexed: 09/14/2023] Open
Abstract
The seminal paper of Crick and Koch (2005) proposed that the claustrum, an enigmatic and thin grey matter structure that lies beside the insular cortex, may be involved in the processing of consciousness. As a result, this otherwise obscure structure has received ever-increasing interest in the search for neural correlates of consciousness. Here we review theories of consciousness and discuss the possible relationship between the claustrum and consciousness. We review relevant experimental evidence collected since the Crick and Koch (2005) paper and consider whether these findings support or contradict their hypothesis. We also explore how future experimental work can be designed to clarify how consciousness emerges from neural activity and to understand the role of the claustrum in consciousness.
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Affiliation(s)
- Yin Siang Liaw
- Neuroscience & Mental Health Program, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - George J. Augustine
- Neuroscience & Mental Health Program, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
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2
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Dourron HM, Strauss C, Hendricks PS. Self-Entropic Broadening Theory: Toward a New Understanding of Self and Behavior Change Informed by Psychedelics and Psychosis. Pharmacol Rev 2022; 74:982-1027. [DOI: 10.1124/pharmrev.121.000514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 06/14/2022] [Accepted: 06/16/2022] [Indexed: 11/22/2022] Open
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3
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Distribution Pattern of the Monoamine Oxidase B Ligand, 18F-THK5351, in the Healthy Brain. Clin Nucl Med 2022; 47:e489-e495. [PMID: 35675140 DOI: 10.1097/rlu.0000000000004272] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND 18F-THK5351 PET estimates the concentrations of monoamine oxidase B (MAO-B) that are preferentially located in astrocytes and can be used to visualize and quantify ongoing astrogliosis. To study images of astrogliosis in neurological disorders, it is essential to understand the detailed binding sites of 18F-THK5351 as the MAO-B ligand under normal conditions. In this study, we examined the detailed distribution pattern of 18F-THK5351 in the healthy brain by comparing 18F-THK5351 uptake between subjects taking and not taking the MAO-B inhibitor. METHODS Ten healthy controls (HCs: 67.4 [SD, 15.1] years) and 4 patients with Parkinson disease taking the MAO-B inhibitor underwent 18F-THK5351 PET. The uptake ratio index (URI) was defined to quantify 18F-THK5351 uptake, using the cerebellum as a reference region. The cerebellar URI was set to zero. RESULTS For HCs, regions with URI ≥1 were preferentially observed in the following order: the striatum, globus pallidus, thalamus, hypothalamus, amygdala, periaqueductal gray, substantia nigra, medulla, hippocampus, and pons. The peak URI values in the corresponding regions were 2.93, 2.47, 2.12, 2.04, 1.84, 1.68, 1.67, 1.37, 1.20, and 1.11, respectively. For all patients with Parkinson disease taking the MAO-B inhibitor, the URI values in all these regions were significantly decreased (Z score >2) and were reduced from 60.4% to 99.9%, compared with HCs. CONCLUSIONS This study presented the detailed distribution pattern of 18F-THK5351 in HCs and suggests that 18F-THK5351 uptake largely reflects MAO-B concentrations under normal conditions.
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4
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Atlas of type 2 dopamine receptors in the human brain: Age and sex dependent variability in a large PET cohort. Neuroimage 2022; 255:119149. [PMID: 35367652 DOI: 10.1016/j.neuroimage.2022.119149] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 03/22/2022] [Accepted: 03/24/2022] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND The dopamine system contributes to a multitude of functions ranging from reward and motivation to learning and movement control, making it a key component in goal-directed behavior. Altered dopaminergic function is observed in neurological and psychiatric conditions. Numerous factors have been proposed to influence dopamine function, but due to small sample sizes and heterogeneous data analysis methods in previous studies their specific and joint contributions remain unresolved. METHODS In this cross-sectional register-based study we investigated how age, sex, body mass index (BMI), as well as cerebral hemisphere and regional volume influence striatal type 2 dopamine receptor (D2R) availability in the human brain. We analyzed a large historical dataset (n=156, 120 males and 36 females) of [11C]raclopride PET scans performed between 2004 and 2018. RESULTS Striatal D2R availability decreased through age for both sexes (2-5 % in striatal ROIs per 10 years) and was higher in females versus males throughout age (7-8% in putamen). BMI and striatal D2R availability were weakly associated. There was no consistent lateralization of striatal D2R. The observed effects were independent of regional volumes. These results were validated using two different spatial normalization methods, and the age and sex effects also replicated in an independent sample (n=135). CONCLUSIONS D2R availability is dependent on age and sex, which may contribute to the vulnerability of neurological and psychiatric conditions involving altering D2R expression.
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5
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Dopamine and fear memory formation in the human amygdala. Mol Psychiatry 2022; 27:1704-1711. [PMID: 34862441 PMCID: PMC9095491 DOI: 10.1038/s41380-021-01400-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 11/12/2021] [Accepted: 11/23/2021] [Indexed: 01/07/2023]
Abstract
Learning which environmental cues that predict danger is crucial for survival and accomplished through Pavlovian fear conditioning. In humans and rodents alike, fear conditioning is amygdala-dependent and rests on similar neurocircuitry. Rodent studies have implicated a causative role for dopamine in the amygdala during fear memory formation, but the role of dopamine in aversive learning in humans is unclear. Here, we show dopamine release in the amygdala and striatum during fear learning in humans. Using simultaneous positron emission tomography and functional magnetic resonance imaging, we demonstrate that the amount of dopamine release is linked to strength of conditioned fear responses and linearly coupled to learning-induced activity in the amygdala. Thus, like in rodents, formation of amygdala-dependent fear memories in humans seems to be facilitated by endogenous dopamine release, supporting an evolutionary conserved neurochemical mechanism for aversive memory formation.
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6
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Richter A, de Boer L, Guitart-Masip M, Behnisch G, Seidenbecher CI, Schott BH. Motivational learning biases are differentially modulated by genetic determinants of striatal and prefrontal dopamine function. J Neural Transm (Vienna) 2021; 128:1705-1720. [PMID: 34302222 PMCID: PMC8536632 DOI: 10.1007/s00702-021-02382-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 07/04/2021] [Indexed: 01/20/2023]
Abstract
Dopaminergic neurotransmission plays a pivotal role in appetitively motivated behavior in mammals, including humans. Notably, action and valence are not independent in motivated tasks, and it is particularly difficult for humans to learn the inhibition of an action to obtain a reward. We have previously observed that the carriers of the DRD2/ANKK1 TaqIA A1 allele, that has been associated with reduced striatal dopamine D2 receptor expression, showed a diminished learning performance when required to learn response inhibition to obtain rewards, a finding that was replicated in two independent cohorts. With our present study, we followed two aims: first, we aimed to replicate our finding on the DRD2/ANKK1 TaqIA polymorphism in a third independent cohort (N = 99) and to investigate the nature of the genetic effects more closely using trial-by-trial behavioral analysis and computational modeling in the combined dataset (N = 281). Second, we aimed to assess a potentially modulatory role of prefrontal dopamine availability, using the widely studied COMT Val108/158Met polymorphism as a proxy. We first report a replication of the above mentioned finding. Interestingly, after combining all three cohorts, exploratory analyses regarding the COMT Val108/158Met polymorphism suggest that homozygotes for the Met allele, which has been linked to higher prefrontal dopaminergic tone, show a lower learning bias. Our results corroborate the importance of genetic variability of the dopaminergic system in individual learning differences of action-valence interaction and, furthermore, suggest that motivational learning biases are differentially modulated by genetic determinants of striatal and prefrontal dopamine function.
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Affiliation(s)
- Anni Richter
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118, Magdeburg, Germany.
| | - Lieke de Boer
- Ageing Research Centre, Karolinska Institute, Stockholm, Sweden
- Max Planck Institute for Human Development, Center for Lifespan Psychology, Berlin, Germany
| | - Marc Guitart-Masip
- Ageing Research Centre, Karolinska Institute, Stockholm, Sweden
- Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, UK
| | - Gusalija Behnisch
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118, Magdeburg, Germany
| | - Constanze I Seidenbecher
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Magdeburg, Germany
| | - Björn H Schott
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Magdeburg, Germany
- Department of Psychiatry and Psychotherapy, University Medicine Göttingen, Göttingen, Germany
- Department of Neurology, University of Magdeburg, Magdeburg, Germany
- German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
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7
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Maeda CT, Takeuchi H, Nouchi R, Yokoyama R, Kotozaki Y, Nakagawa S, Sekiguchi A, Iizuka K, Hanawa S, Araki T, Miyauchi CM, Sakaki K, Nozawa T, Shigeyuki I, Yokota S, Magistro D, Sassa Y, Taki Y, Kawashima R. Brain Microstructural Properties Related to Subjective Well-Being: Diffusion Tensor Imaging Analysis. Soc Cogn Affect Neurosci 2021; 16:1079-1090. [PMID: 33987641 PMCID: PMC8483277 DOI: 10.1093/scan/nsab063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 03/15/2021] [Accepted: 05/13/2021] [Indexed: 12/05/2022] Open
Abstract
Although it is known that health is not merely the absence of disease, the positive aspects of mental health have been less comprehensively researched compared with its negative aspects. Subjective well-being (SWB) is one of the indicators of positive psychology, and high SWB is considered to benefit individuals in multiple ways. However, the neural mechanisms underlying individual differences in SWB remain unclear, particularly in terms of brain microstructural properties as detected by diffusion tensor imaging. The present study aimed to investigate the relationship between measurements of diffusion tensor imaging [mean diffusivity (MD) and fractional anisotropy] and the degree of SWB as measured using a questionnaire. Voxel-based analysis was used to investigate the association between MD and SWB scores in healthy young adults (age, 20.7 ± 1.8 years; 695 males and 514 females). Higher levels of SWB were found to be associated with lower MD in areas surrounding the right putamen, insula, globus pallidus, thalamus and caudate. These results indicated that individual SWB is associated with variability in brain microstructural properties.
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Affiliation(s)
- Chiaki Terao Maeda
- Department of Nuclear Medicine and Radiology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Hikaru Takeuchi
- Division of Developmental Cognitive Neuroscience, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Rui Nouchi
- Department of Cognitive Health Science, Institute of Development, Aging, and Cancer (IDAC), Tohoku University, Sendai, Japan.,Smart Aging Research Center, Tohoku University, Sendai, Japan
| | | | - Yuka Kotozaki
- Division of Clinical research, Medical-Industry Translational Research Center, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Seishu Nakagawa
- Department of Human Brain Science, Institute of Development, Aging and Cancer Tohoku University, Sendai, Japan.,Division of Psychiatry, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Atsushi Sekiguchi
- Department of Behavioral Medicine National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan.,Division of Medical Neuroimaging Analysis, Department of Community Medical Supports, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Kunio Iizuka
- Department of Psychiatry Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Sugiko Hanawa
- Department of Human Brain Science, Institute of Development, Aging and Cancer Tohoku University, Sendai, Japan
| | | | - Carlos Makoto Miyauchi
- Department of Advanced Brain Science, Institute of Development, Aging and Cancer Tohoku University, Sendai, Japan
| | - Kohei Sakaki
- Department of Advanced Brain Science, Institute of Development, Aging and Cancer Tohoku University, Sendai, Japan
| | - Takayuki Nozawa
- Research Institute for the Earth Inclusive Sensing, Tokyo Institute of Technology, Tokyo, Japan
| | - Ikeda Shigeyuki
- Department of Ubiquitous Sensing, Institute of Development, Aging and Cancer Tohoku University, Sendai, Japan
| | - Susumu Yokota
- Faculty of arts and science, Kyushu University, Fukuoka, Japan
| | - Daniele Magistro
- Department of Sport Science, School of Science and Technology Nottingham Trent University, Nottingham, UK
| | - Yuko Sassa
- Division of Developmental Cognitive Neuroscience, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Yasuyuki Taki
- Department of Nuclear Medicine and Radiology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.,Division of Developmental Cognitive Neuroscience, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.,Division of Medical Neuroimaging Analysis, Department of Community Medical Supports, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Ryuta Kawashima
- Division of Developmental Cognitive Neuroscience, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.,Department of Human Brain Science, Institute of Development, Aging and Cancer Tohoku University, Sendai, Japan.,Department of Advanced Brain Science, Institute of Development, Aging and Cancer Tohoku University, Sendai, Japan
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8
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Wong KLL, Nair A, Augustine GJ. Changing the Cortical Conductor's Tempo: Neuromodulation of the Claustrum. Front Neural Circuits 2021; 15:658228. [PMID: 34054437 PMCID: PMC8155375 DOI: 10.3389/fncir.2021.658228] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 03/29/2021] [Indexed: 12/12/2022] Open
Abstract
The claustrum is a thin sheet of neurons that is densely connected to many cortical regions and has been implicated in numerous high-order brain functions. Such brain functions arise from brain states that are influenced by neuromodulatory pathways from the cholinergic basal forebrain, dopaminergic substantia nigra and ventral tegmental area, and serotonergic raphe. Recent revelations that the claustrum receives dense input from these structures have inspired investigation of state-dependent control of the claustrum. Here, we review neuromodulation in the claustrum-from anatomical connectivity to behavioral manipulations-to inform future analyses of claustral function.
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Affiliation(s)
- Kelly L. L. Wong
- Neuroscience and Mental Health Program, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Aditya Nair
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- Computation and Neural Systems, California Institute of Technology, Pasadena, CA, United States
| | - George J. Augustine
- Neuroscience and Mental Health Program, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
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9
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Takamura Y, Kakuta H. In Vivo Receptor Visualization and Evaluation of Receptor Occupancy with Positron Emission Tomography. J Med Chem 2021; 64:5226-5251. [PMID: 33905258 DOI: 10.1021/acs.jmedchem.0c01714] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Positron emission tomography (PET) is useful for noninvasive in vivo visualization of disease-related receptors, for evaluation of receptor occupancy to determine an appropriate drug dosage, and for proof-of-concept of drug candidates in translational research. For these purposes, the specificity of the PET tracer for the target receptor is critical. Here, we review work in this area, focusing on the chemical structures of reported PET tracers, their Ki/Kd values, and the physical properties relevant to target receptor selectivity. Among these physical properties, such as cLogP, cLogD, molecular weight, topological polar surface area, number of hydrogen bond donors, and pKa, we focus especially on LogD and LogP as important physical properties that can be easily compared across a range of studies. We discuss the success of PET tracers in evaluating receptor occupancy and consider likely future developments in the field.
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Affiliation(s)
- Yuta Takamura
- Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 1-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Hiroki Kakuta
- Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 1-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
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10
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Komorowski A, Weidenauer A, Murgaš M, Sauerzopf U, Wadsak W, Mitterhauser M, Bauer M, Hacker M, Praschak-Rieder N, Kasper S, Lanzenberger R, Willeit M. Association of dopamine D 2/3 receptor binding potential measured using PET and [ 11C]-(+)-PHNO with post-mortem DRD 2/3 gene expression in the human brain. Neuroimage 2020; 223:117270. [PMID: 32818617 PMCID: PMC7610745 DOI: 10.1016/j.neuroimage.2020.117270] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 08/12/2020] [Accepted: 08/12/2020] [Indexed: 01/11/2023] Open
Abstract
Open access post-mortem transcriptome atlases such as the Allen Human Brain Atlas (AHBA) can inform us about mRNA expression of numerous proteins of interest across the whole brain, while in vivo protein binding in the human brain can be quantified by means of neuroreceptor positron emission tomography (PET). By combining both modalities, the association between regional gene expression and receptor distribution in the living brain can be approximated. Here, we compare the characteristics of D2 and D3 dopamine receptor distribution by applying the dopamine D2/3 receptor agonist radioligand [11C]-(+)-PHNO and human gene expression data. Since [11C]-(+)-PHNO has a higher affinity for D3 compared to D2 receptors, we hypothesized that there is a stronger relationship between D2/3 non-displaceable binding potentials (BPND) and D3 mRNA expression. To investigate the relationship between D2/3 BPND and mRNA expression of DRD2 and DRD3 we performed [11C]-(+)-PHNO PET scans in 27 healthy subjects (12 females) and extracted gene expression data from the AHBA. We also calculated D2/D3 mRNA expression ratios to imitate the mixed D2/3 signal of [11C]-(+)-PHNO. In accordance with our a priori hypothesis, a strong correlation between [11C]-(+)-PHNO and DRD3 expression was found. However, there was no significant correlation with DRD2 expression. Calculated D2/D3 mRNA expression ratios also showed a positive correlation with [11C]-(+)-PHNO binding, reflecting the mixed D2/3 signal of the radioligand. Our study supports the usefulness of combining gene expression data from open access brain atlases with in vivo imaging data in order to gain more detailed knowledge on neurotransmitter signaling.
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Affiliation(s)
- Arkadiusz Komorowski
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Ana Weidenauer
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Matej Murgaš
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Ulrich Sauerzopf
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Wolfgang Wadsak
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria; Center for Biomarker Research in Medicine (CBmed), Graz, Austria
| | - Markus Mitterhauser
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria; Ludwig Boltzmann Institute for Applied Diagnostics, Vienna, Austria
| | - Martin Bauer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Marcus Hacker
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria
| | - Nicole Praschak-Rieder
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Siegfried Kasper
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
| | - Matthäus Willeit
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
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11
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Freiburghaus T, Svensson JE, Matheson GJ, Plavén-Sigray P, Lundberg J, Farde L, Cervenka S. Low convergent validity of [ 11C]raclopride binding in extrastriatal brain regions: A PET study of within-subject correlations with [ 11C]FLB 457. Neuroimage 2020; 226:117523. [PMID: 33144221 DOI: 10.1016/j.neuroimage.2020.117523] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 10/24/2020] [Accepted: 10/26/2020] [Indexed: 11/16/2022] Open
Abstract
Dopamine D2 receptors (D2-R) in extrastriatal brain regions are of high interest for research in a wide range of psychiatric and neurologic disorders. Pharmacological competition studies and test-retest experiments have shown high validity and reliability of the positron emission tomography (PET) radioligand [11C]FLB 457 for D2-R quantification in extrastriatal brain regions. However, this radioligand is not available at most research centers. Instead, the medium affinity radioligand [11C]raclopride, which has been extensively validated for quantification of D2-R in the high-density region striatum, has been applied also in studies on extrastriatal D2-R. Recently, the validity of this approach has been questioned by observations of low occupancy of [11C]raclopride in extrastriatal regions in a pharmacological competition study with quetiapine. Here, we utilise a data set of 16 healthy control subjects examined with both [11C]raclopride and [11C]FLB 457 to assess the correlation in binding potential (BPND) in extrastriatal brain regions. BPND was quantified using the simplified reference tissue model with cerebellum as reference region. The rank order of mean regional BPND values were similar for both radioligands, and corresponded to previously reported data, both post-mortem and using PET. Nevertheless, weak to moderate within-subject correlations were observed between [11C]raclopride and [11C]FLB 457 BPND extrastriatally (Pearson's R: 0.30-0.56), in contrast to very strong correlations between repeated [11C]FLB 457 measurements (Pearson's R: 0.82-0.98). In comparison, correlations between repeated [11C]raclopride measurements were low to moderate (Pearson's R: 0.28-0.75). These results are likely related to low signal to noise ratio of [11C]raclopride in extrastriatal brain regions, and further strengthen the recommendation that extrastriatal D2-R measures obtained with [11C]raclopride should be interpreted with caution.
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Affiliation(s)
- Tove Freiburghaus
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet and Stockholm Health Care Services, Region Stockholm, Stockholm SE -171 76, Sweden.
| | - Jonas E Svensson
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet and Stockholm Health Care Services, Region Stockholm, Stockholm SE -171 76, Sweden
| | - Granville J Matheson
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet and Stockholm Health Care Services, Region Stockholm, Stockholm SE -171 76, Sweden
| | - Pontus Plavén-Sigray
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet and Stockholm Health Care Services, Region Stockholm, Stockholm SE -171 76, Sweden; Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Johan Lundberg
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet and Stockholm Health Care Services, Region Stockholm, Stockholm SE -171 76, Sweden
| | - Lars Farde
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet and Stockholm Health Care Services, Region Stockholm, Stockholm SE -171 76, Sweden
| | - Simon Cervenka
- Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet and Stockholm Health Care Services, Region Stockholm, Stockholm SE -171 76, Sweden
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12
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In response to the letter “[11C]raclopride and extrastriatal binding to D2/3 receptors”. Neuroimage 2020; 207:116371. [DOI: 10.1016/j.neuroimage.2019.116371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 11/16/2019] [Indexed: 11/23/2022] Open
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13
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Weidenauer A, Bauer M, Sauerzopf U, Bartova L, Nics L, Pfaff S, Philippe C, Berroterán-Infante N, Pichler V, Meyer BM, Rabl U, Sezen P, Cumming P, Stimpfl T, Sitte HH, Lanzenberger R, Mossaheb N, Zimprich A, Rusjan P, Dorffner G, Mitterhauser M, Hacker M, Pezawas L, Kasper S, Wadsak W, Praschak-Rieder N, Willeit M. On the relationship of first-episode psychosis to the amphetamine-sensitized state: a dopamine D 2/3 receptor agonist radioligand study. Transl Psychiatry 2020; 10:2. [PMID: 32066718 PMCID: PMC7026156 DOI: 10.1038/s41398-019-0681-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 10/01/2019] [Accepted: 11/01/2019] [Indexed: 12/21/2022] Open
Abstract
Schizophrenia is characterized by increased behavioral and neurochemical responses to dopamine-releasing drugs. This prompted the hypothesis of psychosis as a state of "endogenous" sensitization of the dopamine system although the exact basis of dopaminergic disturbances and the possible role of prefrontal cortical regulation have remained uncertain. To show that patients with first-episode psychosis release more dopamine upon amphetamine-stimulation than healthy volunteers, and to reveal for the first time that prospective sensitization induced by repeated amphetamine exposure increases dopamine-release in stimulant-naïve healthy volunteers to levels observed in patients, we collected data on amphetamine-induced dopamine release using the dopamine D2/3 receptor agonist radioligand [11C]-(+)-PHNO and positron emission tomography. Healthy volunteers (n = 28, 14 female) underwent a baseline and then a post-amphetamine scan before and after a mildly sensitizing regimen of repeated oral amphetamine. Unmedicated patients with first-episode psychosis (n = 21; 6 female) underwent a single pair of baseline and then post-amphetamine scans. Furthermore, T1 weighted magnetic resonance imaging of the prefrontal cortex was performed. Patients with first-episode psychosis showed larger release of dopamine compared to healthy volunteers. After sensitization of healthy volunteers their dopamine release was significantly amplified and no longer different from that seen in patients. Healthy volunteers showed a negative correlation between prefrontal cortical volume and dopamine release. There was no such relationship after sensitization or in patients. Our data in patients with untreated first-episode psychosis confirm the "endogenous sensitization" hypothesis and support the notion of impaired prefrontal control of the dopamine system in schizophrenia.
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Affiliation(s)
- Ana Weidenauer
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Martin Bauer
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Ulrich Sauerzopf
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Lucie Bartova
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Lukas Nics
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Sarah Pfaff
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Cecile Philippe
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Neydher Berroterán-Infante
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Verena Pichler
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Bernhard M Meyer
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Ulrich Rabl
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Patrick Sezen
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Paul Cumming
- School of Psychology and Counseling and IHBI, Queensland University of Technology, Brisbane, Australia
- Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Thomas Stimpfl
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Harald H Sitte
- Institute of Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Nilufar Mossaheb
- Department of Psychiatry and Psychotherapy, Division of Social Psychiatry, Medical University of Vienna, Vienna, Austria
| | | | - Pablo Rusjan
- Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Toronto, Canada
| | - Georg Dorffner
- Center for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, Vienna, Austria
| | - Markus Mitterhauser
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
- Ludwig Boltzmann Institute Applied Diagnostics, Vienna, Austria
| | - Marcus Hacker
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Lukas Pezawas
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Siegfried Kasper
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Wolfgang Wadsak
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Nicole Praschak-Rieder
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Matthäus Willeit
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.
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Validity and reliability of extrastriatal [11C]raclopride binding quantification in the living human brain. Neuroimage 2019; 202:116143. [DOI: 10.1016/j.neuroimage.2019.116143] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 07/26/2019] [Accepted: 08/28/2019] [Indexed: 01/25/2023] Open
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15
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Pavel B, Menardy F, Rotaru D, Paslaru AC, Acatrinei C, Zagrean L, Popa D, Zagrean AM. Electrical Stimulation in the Claustrum Area Induces a Deepening of Isoflurane Anesthesia in Rat. Brain Sci 2019; 9:brainsci9110304. [PMID: 31683949 PMCID: PMC6895863 DOI: 10.3390/brainsci9110304] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 10/29/2019] [Accepted: 10/30/2019] [Indexed: 11/16/2022] Open
Abstract
The role of the claustrum in consciousness and vigilance states was proposed more than two decades ago; however, its role in anesthesia is not yet understood, and this requires more investigation. The aim of our study was to assess the impact of claustrum electrical stimulation during isoflurane anesthesia in adult rats. The claustrum in the left hemisphere was electrically stimulated using a bipolar tungsten electrode inserted stereotaxically. In order to monitor the anesthetic depth, the electrocorticogram (ECoG) was recorded before, during, and after claustrum stimulation using frontal and parietal epidural electrodes placed over the left hemisphere. After reaching stabilized slow-wave isoflurane anesthesia, twenty stimuli, each of one second duration with ten seconds interstimulus duration, were applied. ECoG analysis has shown that, after a delay from the beginning of stimulation, the slow-wave ECoG signal changed to a transient burst suppression (BS) pattern. Our results show that electrical stimulation of the claustrum area during slow-wave isoflurane anesthesia induces a transitory increase in anesthetic depth, documented by the appearance of a BS ECoG pattern, and suggests a potential role of claustrum in anesthesia.
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Affiliation(s)
- Bogdan Pavel
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania.
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, PSL Research University, 75005 Paris, France.
| | - Fabien Menardy
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, PSL Research University, 75005 Paris, France.
| | - Diana Rotaru
- Department of Neuroimaging, Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE58AF, UK.
| | - Alexandru Catalin Paslaru
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania.
| | - Camelia Acatrinei
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania.
| | - Leon Zagrean
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania.
| | - Daniela Popa
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania.
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, PSL Research University, 75005 Paris, France.
| | - Ana-Maria Zagrean
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania.
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Veselinović T, Vernaleken I, Janouschek H, Cumming P, Paulzen M, Mottaghy FM, Gründer G. The role of striatal dopamine D 2/3 receptors in cognitive performance in drug-free patients with schizophrenia. Psychopharmacology (Berl) 2018; 235:2221-2232. [PMID: 29717334 DOI: 10.1007/s00213-018-4916-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 04/18/2018] [Indexed: 10/17/2022]
Abstract
OBJECTIVE A considerable body of research links cognitive function to dopaminergic transmission in the prefrontal cortex, but less is known about cognition in relation to striatal dopamine D2/3 receptors in unmedicated patients with psychosis. METHODS We investigated this association by obtaining PET recordings with the high-affinity D2/3 antagonist ligand [18F] fallypride in 15 medication-free patients with schizophrenia and 11 healthy controls. On the day of PET scanning, we undertook comprehensive neuropsychological testing and assessment of psychopathology using the Positive and Negative Syndrome Scale (PANSS). RESULTS The patients' performance in cognitive tests was significantly impaired in almost all domains. Irrespective of medication history, the mean [18F] fallypride binding potential (BPND) in the patient group tended to be globally 5-10% higher than that of the control group, but without reaching significance in any brain region. There were significant positive correlations between individual patient performance in the Trail Making Test (TMT(A) and TMT(B)) and Digit-Symbol-Substitution-Test with regional [18F] fallypride BPND, which remained significant after Bonferroni correction for the TMT(A) in caudate nucleus (CN) and for the TMT(B) in CN and putamen. No such correlations were evident in the control group. DISCUSSION The association between better cognitive performance and greater BPND in schizophrenia patients may imply that relatively lower receptor occupancy by endogenous dopamine favors better sparing of cognitive function. Absence of comparable correlations in healthy controls could indicate a greater involvement of signaling at dopamine D2/3 receptors in certain cognitive functions in schizophrenia patients than in healthy controls.
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Affiliation(s)
- Tanja Veselinović
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Pauwelsstr. 30, 52074, Aachen, Germany. .,Jülich Aachen Research Alliance JARA, Translational Brain Medicine, Jülich, Germany.
| | - Ingo Vernaleken
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Pauwelsstr. 30, 52074, Aachen, Germany.,Jülich Aachen Research Alliance JARA, Translational Brain Medicine, Jülich, Germany
| | - Hildegard Janouschek
- Department of Psychiatry and Iowa Neuroscience Institute, Roy J and Lucille A Carver College of Medicine, University of Iowa, Iowa City, IA, USA.,Department of Neurology, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Paul Cumming
- School of Psychology and Counselling and IHBI, Queensland University of Technology, and QIMR-Berghofer Institute, Brisbane, Australia
| | - Michael Paulzen
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Pauwelsstr. 30, 52074, Aachen, Germany.,Jülich Aachen Research Alliance JARA, Translational Brain Medicine, Jülich, Germany.,Alexianer Hospital Aachen, Aachen, Germany
| | - Felix M Mottaghy
- Department of Nuclear Medicine, Medical Faculty, RWTH Aachen University, Aachen, Germany.,Department of Radiology and Nuclear Medicine, Maastricht University Medical Center (MUMC+), Maastricht, The Netherlands
| | - Gerhard Gründer
- Department of Molecular Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
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17
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Yilmaz O, Şengül Y, Şengül HS, Parlakkaya FB, Öztürk A. Investigation of alexithymia and levels of anxiety and depression among patients with restless legs syndrome. Neuropsychiatr Dis Treat 2018; 14:2207-2214. [PMID: 30214210 PMCID: PMC6120575 DOI: 10.2147/ndt.s174552] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PURPOSE The purpose of this study was to examine alexithymia among restless legs syndrome (RLS) patients, compare with healthy controls, and argue the clinical inferences of this relationship. We searched for anxiety and depression and their clinical outcomes among patients and searched whether the results are similar to previous studies. PATIENTS AND METHODS Eighty-seven RLS patients and 88 age, gender, and educationally matched healthy controls were assessed in Bezmialem Foundation University Hospital. RLS patients and healthy controls were assessed with the Sociodemographic Data Form constructed for the present study, 20-item Toronto Alexithymia Scale (TAS-20), Beck Depression Inventory (BDI), and Beck Anxiety Scale (BAS). The patient group was also assessed with the International Restless Legs Syndrome Study Group (IRLSSG) RLS Severity Scale. RESULTS RLS patients were found to have greater TAS-20, BDI, and BAS scores compared with the control group (P < 0.05). RLS severity score was positively correlated with the scores of anxiety and depression scales. However, no significant relationship was found between scores of IRLSSG RLS scale and TAS-20 total and subscale scores. CONCLUSION RLS patients were found to be more alexithymic than healthy controls, whereas no significant relationship was found between RLS severity and levels of alexithymia. Still, alexithymia might be a predictor for early diagnosis and may be considered in the treatment and follow-up of RLS. RLS patients have higher depression and anxiety scores than healthy individuals. Thus, depression and anxiety should be taken into consideration throughout the RLS treatment.
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Affiliation(s)
- Onur Yilmaz
- Bezmialem Foundation University Medical Faculty, Department of Psychiatry, Istanbul, Turkey,
| | - Yildizhan Şengül
- Bezmialem Foundation University Medical Faculty, Department of Neurology, IIstanbul, Turkey
| | - Hakan Serdar Şengül
- Gaziosmanpaşa Taksim Research and Training Hospital, Department of Psychiatry, Istanbul, Turkey
| | - Fatma Büşra Parlakkaya
- Bezmialem Foundation University Medical Faculty, Department of Psychiatry, Istanbul, Turkey,
| | - Ahmet Öztürk
- Bezmialem Foundation University Medical Faculty, Department of Psychiatry, Istanbul, Turkey,
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18
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Takeuchi H, Kawashima R. Mean Diffusivity in the Dopaminergic System and Neural Differences Related to Dopaminergic System. Curr Neuropharmacol 2018; 16:460-474. [PMID: 29119929 PMCID: PMC6018195 DOI: 10.2174/1570159x15666171109124839] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 05/29/2017] [Accepted: 11/07/2017] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The mean diffusivity (MD) parameter obtained by diffusion tensor imaging provides a measure of how freely water molecules move in brain tissue. Greater tissue density conferred by closely arrayed cellular structures is assumed to lower MD by inhibiting the free diffusion of water molecules. METHODS In this paper, we review studies showing MD variation among regions of the brain dopaminergic system (MDDS), especially subcortical structures such as the putamen, caudate nucleus, and globus pallidus, in different conditions with known associations to dopaminergic system function or dysfunction. The methodologies and background related to MD and MDDS are also discussed. RESULTS Past studies indicate that MDDS is sensitive to pathological derangement of dopaminergic activity, neural changes caused by cognitive and pharmacological interventions that are known to affect the dopaminergic system, and individual character traits related to dopaminergic function. CONCLUSION These results suggest that MDDS can be one useful tool to tap the neural differences related to the dopaminergic system.
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Affiliation(s)
- Hikaru Takeuchi
- Address correspondence to this author at the Division of Developmental Cognitive Neuroscience, IDAC, Tohoku University, 4-1 Seiryo-cho, Aoba-ku, Sendai 980-8575, Japan; Tel/Fax: +81-22-717-7988;, E-mail:
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19
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Wilbertz G, Delgado MR, Tebartz Van Elst L, Maier S, Philipsen A, Blechert J. Neural response during anticipation of monetary loss is elevated in adult attention deficit hyperactivity disorder. World J Biol Psychiatry 2017; 18:268-278. [PMID: 26508322 DOI: 10.3109/15622975.2015.1112032] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVES Risky behaviour seriously impacts the life of adult patients with attention deficit hyperactivity disorder (ADHD). Such behaviours have often been attributed to their exaggerated reward seeking, but dysfunctional anticipation of negative outcomes might also play a role. METHODS The present study compared adult patients with ADHD (n = 28) with matched healthy controls (n = 28) during anticipation of monetary losses versus gains while undergoing functional magnetic resonance imaging (fMRI) and skin conductance recording. RESULTS Skin conductance was higher during anticipation of losses compared to gains in both groups. Affective ratings of predictive cues did not differ between groups. ADHD patients showed increased activity in bilateral amygdalae, left anterior insula (region of interest analysis) and left temporal pole (whole brain analysis) compared to healthy controls during loss versus gain anticipation. In the ADHD group higher insula and temporal pole activations went along with more negative affective ratings. CONCLUSIONS Neural correlates of loss anticipation are not blunted but rather increased in ADHD, possibly due to a life history of repeated failures and the respective environmental sanctions. Behavioural adaptations to such losses, however, might differentiate them from controls: future research should study whether negative affect might drive more risk seeking than risk avoidance.
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Affiliation(s)
- Gregor Wilbertz
- a Department of Psychology , University of Freiburg , Freiburg , Germany.,b Department of Psychiatry and Psychotherapy, Section for Experimental Neuropsychiatry , University Medical Centre Freiburg , Freiburg , Germany.,c Department of Psychiatry and Psychotherapy , Charité - Universitätsmedizin Berlin , Berlin , Germany
| | - Mauricio R Delgado
- d Department of Psychology , Rutgers University , Newark , NJ 07102 , USA
| | - Ludger Tebartz Van Elst
- b Department of Psychiatry and Psychotherapy, Section for Experimental Neuropsychiatry , University Medical Centre Freiburg , Freiburg , Germany
| | - Simon Maier
- b Department of Psychiatry and Psychotherapy, Section for Experimental Neuropsychiatry , University Medical Centre Freiburg , Freiburg , Germany
| | - Alexandra Philipsen
- b Department of Psychiatry and Psychotherapy, Section for Experimental Neuropsychiatry , University Medical Centre Freiburg , Freiburg , Germany.,e Medical Campus University of Oldenburg, School of Medicine and Health Sciences , Psychiatry and Psychotherapy - University Hospital , Karl-Jaspers-Klinik, Bad Zwischenahn , Germany
| | - Jens Blechert
- f Center for Cognitive Neuroscience, University of Salzburg , Salzburg , Austria.,g Department of Psychology, University of Salzburg , Salzburg , Austria
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20
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Milella MS, Fotros A, Gravel P, Casey KF, Larcher K, Verhaeghe JA, Cox SM, Reader AJ, Dagher A, Benkelfat C, Leyton M. Cocaine cue-induced dopamine release in the human prefrontal cortex. J Psychiatry Neurosci 2016; 41:322-30. [PMID: 26900792 PMCID: PMC5008921 DOI: 10.1503/jpn.150207] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Accumulating evidence indicates that drug-related cues can induce dopamine (DA) release in the striatum of substance abusers. Whether these same cues provoke DA release in the human prefrontal cortex remains unknown. METHODS We used high-resolution positron emission tomography with [18F]fallypride to measure cortical and striatal DA D2/3 receptor availability in the presence versus absence of drug-related cues in volunteers with current cocaine dependence. RESULTS Twelve individuals participated in our study. Among participants reporting a craving response (9 of 12), exposure to the cocaine cues significantly decreased [18F]fallypride binding potential (BPND) values in the medial orbitofrontal cortex and striatum. In all 12 participants, individual differences in the magnitude of craving correlated with BPND changes in the medial orbitofrontal cortex, dorsolateral prefrontal cortex, anterior cingulate, and striatum. Consistent with the presence of autoreceptors on mesostriatal but not mesocortical DA cell bodies, midbrain BPND values were significantly correlated with changes in BPND within the striatum but not the cortex. The lower the midbrain D2 receptor levels, the greater the striatal change in BPND and self-reported craving. LIMITATIONS Limitations of this study include its modest sample size, with only 2 female participants. Newer tracers might have greater sensitivity to cortical DA release. CONCLUSION In people with cocaine use disorders, the presentation of drug-related cues induces DA release within cortical and striatal regions. Both effects are associated with craving, but only the latter is regulated by midbrain autoreceptors. Together, the results suggest that cortical and subcortical DA responses might both influence drug-focused incentive motivational states, but with separate regulatory mechanisms.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Marco Leyton
- Correspondence to: M. Leyton, Department of Psychiatry, McGill University, 1033 Pine Ave. West, Montreal QC, Canada, H3A 1A1;
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21
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Takeuchi H, Taki Y, Sekiguchi A, Nouchi R, Kotozaki Y, Nakagawa S, Miyauchi CM, Iizuka K, Yokoyama R, Shinada T, Yamamoto Y, Hanawa S, Araki T, Kunitoki K, Sassa Y, Kawashima R. Mean diffusivity of basal ganglia and thalamus specifically associated with motivational states among mood states. Brain Struct Funct 2016; 222:1027-1037. [PMID: 27364694 DOI: 10.1007/s00429-016-1262-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 06/22/2016] [Indexed: 11/28/2022]
Abstract
Previously, we proposed that the mean diffusivity (MD), a measure of diffusion tensor imaging (DTI) in areas of the dopaminergic system (MDDS), is associated with motivation. In this study, we tested if and how the motivational state is associated with MD in comparison with other mood states. We also tested the associations of these mood states with multiple cognitive functions. We examined these issues in 766 right-handed healthy young adults. We employed analyses of MD and a psychological measure of the profile of mood states (POMS) as well as multiple cognitive functions. We detected associations between the higher Vigor subscale of POMS and lower MD in the right globus pallidum, right putamen to right posterior insula, right caudate body, and right thalamus, and these associations were highly specific to the Vigor subscale. Similarly, the association of the motivational state with creativity measured by divergent thinking (CMDT) was rather specific and prominent compared with that of the other mood states and cognitive functions. In conclusion, when affective states are finely divided, only the motivational state is associated with MD in the areas related to the dopaminergic system, and psychological mechanisms that had been associated with dopaminergic system (CMDT). These results suggest that these mechanisms specifically contribute to the motivational state and not to the other states, such as depression and anxiety.
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Affiliation(s)
- Hikaru Takeuchi
- Division of Developmental Cognitive Neuroscience, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-cho, Aoba-ku, Sendai, 980-8575, Japan.
| | - Yasuyuki Taki
- Division of Developmental Cognitive Neuroscience, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-cho, Aoba-ku, Sendai, 980-8575, Japan.,Division of Medical Neuroimaging Analysis, Department of Community Medical Supports, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan.,Department of Radiology and Nuclear Medicine, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Atsushi Sekiguchi
- Division of Medical Neuroimaging Analysis, Department of Community Medical Supports, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan.,Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Rui Nouchi
- Human and Social Response Research Division, International Research Institute of Disaster Science, Tohoku University, Sendai, Japan
| | - Yuka Kotozaki
- Division of Clinical research, Medical-Industry Translational Research Center, Fukushima Medical University, School of Medicine, Fukushima, Japan
| | - Seishu Nakagawa
- Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Carlos Makoto Miyauchi
- Department of General Systems Studies, Graduate School of Arts and Sciences, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Kunio Iizuka
- Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Ryoichi Yokoyama
- Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.,Japan Society for the Promotion of Science, Tokyo, Japan
| | - Takamitsu Shinada
- Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Yuki Yamamoto
- Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Sugiko Hanawa
- Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Tsuyoshi Araki
- Smart Aging International Research Center, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | | | - Yuko Sassa
- Division of Developmental Cognitive Neuroscience, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-cho, Aoba-ku, Sendai, 980-8575, Japan
| | - Ryuta Kawashima
- Division of Developmental Cognitive Neuroscience, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-cho, Aoba-ku, Sendai, 980-8575, Japan.,Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.,Division of Clinical research, Medical-Industry Translational Research Center, Fukushima Medical University, School of Medicine, Fukushima, Japan
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22
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Hegeman DJ, Hong ES, Hernández VM, Chan CS. The external globus pallidus: progress and perspectives. Eur J Neurosci 2016; 43:1239-65. [PMID: 26841063 PMCID: PMC4874844 DOI: 10.1111/ejn.13196] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 01/20/2016] [Accepted: 01/27/2016] [Indexed: 12/12/2022]
Abstract
The external globus pallidus (GPe) of the basal ganglia is in a unique and powerful position to influence processing of motor information by virtue of its widespread projections to all basal ganglia nuclei. Despite the clinical importance of the GPe in common motor disorders such as Parkinson's disease, there is only limited information about its cellular composition and organizational principles. In this review, recent advances in the understanding of the diversity in the molecular profile, anatomy, physiology and corresponding behaviour during movement of GPe neurons are described. Importantly, this study attempts to build consensus and highlight commonalities of the cellular classification based on existing but contentious literature. Additionally, an analysis of the literature concerning the intricate reciprocal loops formed between the GPe and major synaptic partners, including both the striatum and the subthalamic nucleus, is provided. In conclusion, the GPe has emerged as a crucial node in the basal ganglia macrocircuit. While subtleties in the cellular makeup and synaptic connection of the GPe create new challenges, modern research tools have shown promise in untangling such complexity, and will provide better understanding of the roles of the GPe in encoding movements and their associated pathologies.
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Affiliation(s)
- Daniel J Hegeman
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Ellie S Hong
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Vivian M Hernández
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - C Savio Chan
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
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Okita K, Ghahremani DG, Payer DE, Robertson CL, Mandelkern MA, London ED. Relationship of Alexithymia Ratings to Dopamine D2-type Receptors in Anterior Cingulate and Insula of Healthy Control Subjects but Not Methamphetamine-Dependent Individuals. Int J Neuropsychopharmacol 2015; 19:pyv129. [PMID: 26657175 PMCID: PMC4886668 DOI: 10.1093/ijnp/pyv129] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 11/25/2015] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Individuals with substance-use disorders exhibit emotional problems, including deficits in emotion recognition and processing, and this class of disorders also has been linked to deficits in dopaminergic markers in the brain. Because associations between these phenomena have not been explored, we compared a group of recently abstinent methamphetamine-dependent individuals (n=23) with a healthy-control group (n=17) on dopamine D2-type receptor availability, measured using positron emission tomography with [(18)F]fallypride. METHODS The anterior cingulate and anterior insular cortices were selected as the brain regions of interest, because they receive dopaminergic innervation and are thought to be involved in emotion awareness and processing. The Toronto Alexithymia Scale, which includes items that assess difficulty in identifying and describing feelings as well as externally oriented thinking, was administered, and the scores were tested for association with D2-type receptor availability. RESULTS Relative to controls, methamphetamine-dependent individuals showed higher alexithymia scores, reporting difficulty in identifying feelings. The groups did not differ in D2-type receptor availability in the anterior cingulate or anterior insular cortices, but a significant interaction between group and D2-type receptor availability in both regions, on self-report score, reflected significant positive correlations in the control group (higher receptor availability linked to higher alexithymia) but nonsignificant, negative correlations (lower receptor availability linked to higher alexithymia) in methamphetamine-dependent subjects. CONCLUSIONS The results suggest that neurotransmission through D2-type receptors in the anterior cingulate and anterior insular cortices influences capacity of emotion processing in healthy people but that this association is absent in individuals with methamphetamine dependence.
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Affiliation(s)
- Kyoji Okita
- Department of Psychiatry and Biobehavioral Sciences (Drs Okita, Ghahremani, and London), Department of Molecular and Medical Pharmacology (Drs Robertson and London), and Brain Research Institute (Dr London), University of California Los Angeles, Los Angeles, CA; Addiction Imaging Research Group, Centre for Addiction and Mental Health, Toronto, Ontario, Canada (Dr Payer); Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada (Dr Payer); Department of Research, VA Greater Los Angeles Healthcare System, Los Angeles, CA (Drs Okita, Robertson, Mandelkern, and London); Department of Physics, University of California Irvine, Irvine, CA (Dr Mandelkern)
| | - Dara G Ghahremani
- Department of Psychiatry and Biobehavioral Sciences (Drs Okita, Ghahremani, and London), Department of Molecular and Medical Pharmacology (Drs Robertson and London), and Brain Research Institute (Dr London), University of California Los Angeles, Los Angeles, CA; Addiction Imaging Research Group, Centre for Addiction and Mental Health, Toronto, Ontario, Canada (Dr Payer); Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada (Dr Payer); Department of Research, VA Greater Los Angeles Healthcare System, Los Angeles, CA (Drs Okita, Robertson, Mandelkern, and London); Department of Physics, University of California Irvine, Irvine, CA (Dr Mandelkern)
| | - Doris E Payer
- Department of Psychiatry and Biobehavioral Sciences (Drs Okita, Ghahremani, and London), Department of Molecular and Medical Pharmacology (Drs Robertson and London), and Brain Research Institute (Dr London), University of California Los Angeles, Los Angeles, CA; Addiction Imaging Research Group, Centre for Addiction and Mental Health, Toronto, Ontario, Canada (Dr Payer); Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada (Dr Payer); Department of Research, VA Greater Los Angeles Healthcare System, Los Angeles, CA (Drs Okita, Robertson, Mandelkern, and London); Department of Physics, University of California Irvine, Irvine, CA (Dr Mandelkern)
| | - Chelsea L Robertson
- Department of Psychiatry and Biobehavioral Sciences (Drs Okita, Ghahremani, and London), Department of Molecular and Medical Pharmacology (Drs Robertson and London), and Brain Research Institute (Dr London), University of California Los Angeles, Los Angeles, CA; Addiction Imaging Research Group, Centre for Addiction and Mental Health, Toronto, Ontario, Canada (Dr Payer); Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada (Dr Payer); Department of Research, VA Greater Los Angeles Healthcare System, Los Angeles, CA (Drs Okita, Robertson, Mandelkern, and London); Department of Physics, University of California Irvine, Irvine, CA (Dr Mandelkern)
| | - Mark A Mandelkern
- Department of Psychiatry and Biobehavioral Sciences (Drs Okita, Ghahremani, and London), Department of Molecular and Medical Pharmacology (Drs Robertson and London), and Brain Research Institute (Dr London), University of California Los Angeles, Los Angeles, CA; Addiction Imaging Research Group, Centre for Addiction and Mental Health, Toronto, Ontario, Canada (Dr Payer); Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada (Dr Payer); Department of Research, VA Greater Los Angeles Healthcare System, Los Angeles, CA (Drs Okita, Robertson, Mandelkern, and London); Department of Physics, University of California Irvine, Irvine, CA (Dr Mandelkern)
| | - Edythe D London
- Department of Psychiatry and Biobehavioral Sciences (Drs Okita, Ghahremani, and London), Department of Molecular and Medical Pharmacology (Drs Robertson and London), and Brain Research Institute (Dr London), University of California Los Angeles, Los Angeles, CA; Addiction Imaging Research Group, Centre for Addiction and Mental Health, Toronto, Ontario, Canada (Dr Payer); Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada (Dr Payer); Department of Research, VA Greater Los Angeles Healthcare System, Los Angeles, CA (Drs Okita, Robertson, Mandelkern, and London); Department of Physics, University of California Irvine, Irvine, CA (Dr Mandelkern).
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Alakurtti K, Johansson JJ, Joutsa J, Laine M, Bäckman L, Nyberg L, Rinne JO. Long-term test-retest reliability of striatal and extrastriatal dopamine D2/3 receptor binding: study with [(11)C]raclopride and high-resolution PET. J Cereb Blood Flow Metab 2015; 35:1199-205. [PMID: 25853904 PMCID: PMC4640276 DOI: 10.1038/jcbfm.2015.53] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 02/27/2015] [Accepted: 03/02/2015] [Indexed: 01/13/2023]
Abstract
We measured the long-term test-retest reliability of [(11)C]raclopride binding in striatal subregions, the thalamus and the cortex using the bolus-plus-infusion method and a high-resolution positron emission scanner. Seven healthy male volunteers underwent two positron emission tomography (PET) [(11)C]raclopride assessments, with a 5-week retest interval. D2/3 receptor availability was quantified as binding potential using the simplified reference tissue model. Absolute variability (VAR) and intraclass correlation coefficient (ICC) values indicated very good reproducibility for the striatum and were 4.5%/0.82, 3.9%/0.83, and 3.9%/0.82, for the caudate nucleus, putamen, and ventral striatum, respectively. Thalamic reliability was also very good, with VAR of 3.7% and ICC of 0.92. Test-retest data for cortical areas showed good to moderate reproducibility (6.1% to 13.1%). Our results are in line with previous test-retest studies of [(11)C]raclopride binding in the striatum. A novel finding is the relatively low variability of [(11)C]raclopride binding, providing suggestive evidence that extrastriatal D2/3 binding can be studied in vivo with [(11)C]raclopride PET to be verified in future studies.
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Affiliation(s)
- Kati Alakurtti
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland
| | - Jarkko J Johansson
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland
| | - Juho Joutsa
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland
| | - Matti Laine
- Department of Psychology and Logopedics, Abo Akademi University, Turku, Finland
| | - Lars Bäckman
- Aging Research Center, Karolinska Institute, Stockholm, Sweden
| | - Lars Nyberg
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Juha O Rinne
- 1] Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland [2] Department of Neurology, Turku University Hospital, Turku, Finland
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Patru MC, Reser DH. A New Perspective on Delusional States - Evidence for Claustrum Involvement. Front Psychiatry 2015; 6:158. [PMID: 26617532 PMCID: PMC4639708 DOI: 10.3389/fpsyt.2015.00158] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 10/26/2015] [Indexed: 12/21/2022] Open
Abstract
Delusions are a hallmark positive symptom of schizophrenia, although they are also associated with a wide variety of other psychiatric and neurological disorders. The heterogeneity of clinical presentation and underlying disease, along with a lack of experimental animal models, make delusions exceptionally difficult to study in isolation, either in schizophrenia or other diseases. To date, no detailed studies have focused specifically on the neural mechanisms of delusion, although some studies have reported characteristic activation of specific brain areas or networks associated with them. Here, we present a novel hypothesis and extant supporting evidence implicating the claustrum, a relatively poorly understood forebrain nucleus, as a potential common center for delusional states.
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Affiliation(s)
- Maria Cristina Patru
- Department of Psychiatry, Hôpitaux Universitaires de Genève , Geneve , Switzerland
| | - David H Reser
- Department of Physiology, Monash University , Melbourne , Australia
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Therapeutic window for striatal dopamine D(2/3) receptor occupancy in older patients with schizophrenia: a pilot PET study. Am J Geriatr Psychiatry 2014; 22:1007-16. [PMID: 25217025 DOI: 10.1016/j.jagp.2013.01.045] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2011] [Revised: 01/21/2012] [Accepted: 02/27/2012] [Indexed: 11/23/2022]
Abstract
OBJECTIVE In younger patients with schizophrenia, positron emission tomography (PET) studies have identified a therapeutic window of striatal dopamine D(2/3) receptor occupancy of 65%-80%. This type of empirical information is not available in late life. Our primary aim was to assess the effect of changes in D(2/3) relative receptor occupancy (RRO) on clinical outcomes in this population. DESIGN Open-label intervention. SETTING Centre for Addiction and Mental Health, Toronto. PARTICIPANTS Subjects with schizophrenia age 50 years or more who were clinically stable and previously maintained on oral risperidone for D(2/3) RRO in dorsal putamen was assessed, using the region of interest analysis of [¹¹C]raclopride PET scans, before and after the dose reduction. Clinical assessments included the Positive and Negative Syndrome Scale and the Simpson-Angus Scale. RESULTS Nine subjects (mean ± SD age: 58 ± 7 years; mean ± SD baseline risperidone dose: 3.4 ± 1.6 mg/day) participated in the study. Extrapyramidal symptoms (EPS) were present in six subjects and were associated with 70% or more D(2/3) RRO in the putamen (range: 70%-87%). Following the dose reduction, EPS resolved in five subjects. Two subjects experienced a clinical worsening at 52% and at less than 50% D(2/3) RRO. CONCLUSION EPS diminished less than 70% D(2/3) RRO, which suggests a lower therapeutic window for older patients with schizophrenia than that for younger patients. Although these findings have to be replicated in a larger sample, they have important implications for future drug development and clinical guidelines in late-life schizophrenia.
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Ishibashi K, Robertson CL, Mandelkern MA, Morgan AT, London ED. The simplified reference tissue model with 18F-fallypride positron emission tomography: choice of reference region. Mol Imaging 2014; 12. [PMID: 24447617 DOI: 10.2310/7290.2013.00065] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The development of high-affinity radiotracers for positron emission tomography (PET) has allowed for quantification of dopamine receptors in extrastriatal and striatal regions of the brain. As these new radiotracers have distinctly different kinetic properties than their predecessors, it is important to examine the suitability of kinetic models to represent their uptake, distribution, and in vivo washout. Using the simplified reference tissue model, we investigated the influence of reference region choice on the striatal binding potential of 18F-fallypride, a high-affinity dopamine D2/D3 receptor ligand. We compared the use of the visual cortex and a white matter region (superior longitudinal fasciculus) to the cerebellum, a commonly used reference tissue, in a PET-fallypride study of healthy and methamphetamine-dependent subjects. Compared to the cerebellum, use of the visual cortex produced significantly greater sample variance in binding potential relative to nondisplaceable uptake (BP(ND)). Use of the white matter region was associated with BP(ND) values and sample variance similar to those obtained with the cerebellum and a larger effect size for the group differences in striatal BP(ND) between healthy and methamphetamine-dependent subjects. Our results do not support the use of the visual cortex as a reference region in 18F-fallypride studies and suggest that white matter may be a reasonable alternative to the cerebellum as it displays similar statistical and kinetic properties.
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Gass N, Schwarz AJ, Sartorius A, Cleppien D, Zheng L, Schenker E, Risterucci C, Meyer-Lindenberg A, Weber-Fahr W. Haloperidol modulates midbrain-prefrontal functional connectivity in the rat brain. Eur Neuropsychopharmacol 2013; 23:1310-9. [PMID: 23165219 DOI: 10.1016/j.euroneuro.2012.10.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Revised: 09/21/2012] [Accepted: 10/24/2012] [Indexed: 10/27/2022]
Abstract
Dopamine D₂ receptor antagonists effectively reduce positive symptoms in schizophrenia, implicating abnormal dopaminergic neurotransmission as an underlying mechanism of psychosis. Despite the well-established, albeit incomplete, clinical efficacies of D₂ antagonists, no studies have examined their effects on functional interaction between brain regions. We hypothesized that haloperidol, a widely used antipsychotic and D₂ antagonist, would modulate functional connectivity in dopaminergic circuits. Ten male Sprague-Dawley rats received either haloperidol (1 mg/kg, s.c.) or the same volume of saline a week apart. Resting-state functional magnetic resonance imaging data were acquired 20 min after injection. Connectivity analyses were performed using two complementary approaches: correlation analysis between 44 atlas-derived regions of interest, and seed-based connectivity mapping. In the presence of haloperidol, reduced correlation was observed between the substantia nigra and several brain regions, notably the cingulate and prefrontal cortices, posterodorsal hippocampus, ventral pallidum, and motor cortex. Haloperidol induced focal changes in functional connectivity were found to be the most strongly associated with ascending dopamine projections. These included reduced connectivity between the midbrain and the medial prefrontal cortex and hippocampus, possibly relating to its therapeutic action, and decreased coupling between substantia nigra and motor areas, which may reflect dyskinetic effects. These data may help in further characterizing the functional circuits modulated by antipsychotics that could be targeted by innovative drug treatments.
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Affiliation(s)
- Natalia Gass
- Department of Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Germany.
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Pu S, Nakagome K, Yamada T, Yokoyama K, Itakura M, Satake T, Ishida H, Nagata I, Kaneko K. Association between subjective well-being and prefrontal function during a cognitive task in schizophrenia: a multi-channel near-infrared spectroscopy study. Schizophr Res 2013; 149:180-5. [PMID: 23849884 DOI: 10.1016/j.schres.2013.06.036] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 05/25/2013] [Accepted: 06/22/2013] [Indexed: 11/28/2022]
Abstract
The purpose of this study was to examine the relationship between subjective well-being and prefrontal function during a cognitive task in schizophrenia. Twenty-four patients with clinically stable schizophrenia participated in the study. We measured the change in hemoglobin concentration in the prefrontal region during a verbal fluency task (VFT) by using 52-channel near-infrared spectroscopy (NIRS). The subjective well-being of participants was assessed using the Subjective Well-being under Neuroleptic drug treatment Short form (SWNS). A significant positive relationship was observed between the SWNS score and frontopolar, left ventrolateral, and bilateral dorsolateral prefrontal function during the VFT. These results suggest that the frontopolar and left ventrolateral and bilateral dorsolateral prefrontal cortical regions are associated with the subjective well-being of clinically stable patients with schizophrenia and that NIRS may be an efficient medical tool for monitoring these characteristics.
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Affiliation(s)
- Shenghong Pu
- Division of Neuropsychiatry, Department of Brain and Neuroscience, Tottori University Faculty of Medicine, 36-1 Nishi-cho, Yonago, Tottori 683-8504, Japan.
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Neurovascular coupling to D2/D3 dopamine receptor occupancy using simultaneous PET/functional MRI. Proc Natl Acad Sci U S A 2013; 110:11169-74. [PMID: 23723346 DOI: 10.1073/pnas.1220512110] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This study employed simultaneous neuroimaging with positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) to demonstrate the relationship between changes in receptor occupancy measured by PET and changes in brain activity inferred by fMRI. By administering the D2/D3 dopamine receptor antagonist [(11)C]raclopride at varying specific activities to anesthetized nonhuman primates, we mapped associations between changes in receptor occupancy and hemodynamics [cerebral blood volume (CBV)] in the domains of space, time, and dose. Mass doses of raclopride above tracer levels caused increases in CBV and reductions in binding potential that were localized to the dopamine-rich striatum. Moreover, similar temporal profiles were observed for specific binding estimates and changes in CBV. Injection of graded raclopride mass doses revealed a monotonic coupling between neurovascular responses and receptor occupancies. The distinct CBV magnitudes between putamen and caudate at matched occupancies approximately matched literature differences in basal dopamine levels, suggesting that the relative fMRI measurements reflect basal D2/D3 dopamine receptor occupancy. These results can provide a basis for models that relate dopaminergic occupancies to hemodynamic changes in the basal ganglia. Overall, these data demonstrate the utility of simultaneous PET/fMRI for investigations of neurovascular coupling that correlate neurochemistry with hemodynamic changes in vivo for any receptor system with an available PET tracer.
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Ettinger U, Corr PJ, Mofidi A, Williams SCR, Kumari V. Dopaminergic basis of the psychosis-prone personality investigated with functional magnetic resonance imaging of procedural learning. Front Hum Neurosci 2013; 7:130. [PMID: 23596404 PMCID: PMC3626071 DOI: 10.3389/fnhum.2013.00130] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2012] [Accepted: 03/25/2013] [Indexed: 11/13/2022] Open
Abstract
Previous evidence shows a reliable association between psychosis-prone (especially schizotypal) personality traits and performance on dopamine (DA)-sensitive tasks (e.g., prepulse inhibition and antisaccade). Here, we used blood oxygen level-dependent (BOLD) fMRI and an established procedural learning (PL) task to examine the dopaminergic basis of two aspects of psychosis-proneness (specific schizotypy and general psychoticism). Thirty healthy participants (final N = 26) underwent fMRI during a blocked, periodic sequence-learning task which, in previous studies, has been shown to reveal impaired performance in schizophrenia patients given drugs blocking the DA D2 receptor subtype (DRD2), and to correspond with manipulation of DA activity and elicit fronto-striatal-cerebellar activity in healthy people. Psychosis-proneness was indexed by the Psychoticism (P) scale of the Eysenck Personality Questionnaire-Revised (EPQ-R; 1991) and the Schizotypal Personality Scale (STA; 1984). EPQ-R Extraversion and Neuroticism scores were also examined to establish discriminant validity. We found a positive correlation between the two psychosis-proneness measures (r = 0.43), and a robust and unique positive association between EPQ-R P and BOLD signal in the putamen, caudate, thalamus, insula, and frontal regions. STA schizotypy score correlated positively with activity in the right middle temporal gyrus. As DA is a key transmitter in the basal ganglia, and the thalamus contains the highest levels of DRD2 receptors of all extrastriatal regions, our results support a dopaminergic basis of psychosis-proneness as measured by the EPQ-R Psychoticism.
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Affiliation(s)
- Ulrich Ettinger
- Department of Psychology, University of BonnBonn, Germany
- Department of Neuroimaging, Institute of Psychiatry, King's College LondonLondon, UK
| | | | - Ardeshier Mofidi
- Department of Psychology, Institute of Psychiatry, King's College LondonLondon, UK
| | - Steven C. R. Williams
- Department of Neuroimaging, Institute of Psychiatry, King's College LondonLondon, UK
| | - Veena Kumari
- Department of Psychology, Institute of Psychiatry, King's College LondonLondon, UK
- NIHR Biomedical Research Centre for Mental Health, The Institute of Psychiatry, South London and Maudsley NHS TrustLondon, UK
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Simonyan K, Herscovitch P, Horwitz B. Speech-induced striatal dopamine release is left lateralized and coupled to functional striatal circuits in healthy humans: a combined PET, fMRI and DTI study. Neuroimage 2012; 70:21-32. [PMID: 23277111 DOI: 10.1016/j.neuroimage.2012.12.042] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Revised: 11/19/2012] [Accepted: 12/18/2012] [Indexed: 01/17/2023] Open
Abstract
Considerable progress has been recently made in understanding the brain mechanisms underlying speech and language control. However, the neurochemical underpinnings of normal speech production remain largely unknown. We investigated the extent of striatal endogenous dopamine release and its influences on the organization of functional striatal speech networks during production of meaningful English sentences using a combination of positron emission tomography (PET) with the dopamine D(2)/D(3) receptor radioligand [(11)C]raclopride and functional MRI (fMRI). In addition, we used diffusion tensor tractography (DTI) to examine the extent of dopaminergic modulatory influences on striatal structural network organization. We found that, during sentence production, endogenous dopamine was released in the ventromedial portion of the dorsal striatum, in both its associative and sensorimotor functional divisions. In the associative striatum, speech-induced dopamine release established a significant relationship with neural activity and influenced the left-hemispheric lateralization of striatal functional networks. In contrast, there were no significant effects of endogenous dopamine release on the lateralization of striatal structural networks. Our data provide the first evidence for endogenous dopamine release in the dorsal striatum during normal speaking and point to the possible mechanisms behind the modulatory influences of dopamine on the organization of functional brain circuits controlling normal human speech.
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Affiliation(s)
- Kristina Simonyan
- Department of Neurology, Mount Sinai School of Medicine, New York, NY 10029, USA.
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Sun J, Xu J, Cairns NJ, Perlmutter JS, Mach RH. Dopamine D1, D2, D3 receptors, vesicular monoamine transporter type-2 (VMAT2) and dopamine transporter (DAT) densities in aged human brain. PLoS One 2012; 7:e49483. [PMID: 23185343 PMCID: PMC3504049 DOI: 10.1371/journal.pone.0049483] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Accepted: 10/11/2012] [Indexed: 11/18/2022] Open
Abstract
The dopamine D(1), D(2), D(3) receptors, vesicular monoamine transporter type-2 (VMAT2), and dopamine transporter (DAT) densities were measured in 11 aged human brains (aged 77-107.8, mean: 91 years) by quantitative autoradiography. The density of D(1) receptors, VMAT2, and DAT was measured using [(3)H]SCH23390, [(3)H]dihydrotetrabenazine, and [(3)H]WIN35428, respectively. The density of D(2) and D(3) receptors was calculated using the D(3)-preferring radioligand, [(3)H]WC-10 and the D(2)-preferring radioligand [(3)H]raclopride using a mathematical model developed previously by our group. Dopamine D(1), D(2), and D(3) receptors are extensively distributed throughout striatum; the highest density of D(3) receptors occurred in the nucleus accumbens (NAc). The density of the DAT is 10-20-fold lower than that of VMAT2 in striatal regions. Dopamine D(3) receptor density exceeded D(2) receptor densities in extrastriatal regions, and thalamus contained a high level of D(3) receptors with negligible D(2) receptors. The density of dopamine D(1) linearly correlated with D(3) receptor density in the thalamus. The density of the DAT was negligible in the extrastriatal regions whereas the VMAT2 was expressed in moderate density. D(3) receptor and VMAT2 densities were in similar level between the aged human and aged rhesus brain samples, whereas aged human brain samples had lower range of densities of D(1) and D(2) receptors and DAT compared with the aged rhesus monkey brain. The differential density of D(3) and D(2) receptors in human brain will be useful in the interpretation of PET imaging studies in human subjects with existing radiotracers, and assist in the validation of newer PET radiotracers having a higher selectivity for dopamine D(2) or D(3) receptors.
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Affiliation(s)
- Jianjun Sun
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Jinbin Xu
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Nigel J. Cairns
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Joel S. Perlmutter
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Neurobiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Occupational Therapy, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Physical Therapy, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Robert H. Mach
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Cell Biology amd Physiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri, United States of America
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Striatal and extrastriatal dopamine D₂ receptor occupancy by the partial agonist antipsychotic drug aripiprazole in the human brain: a positron emission tomography study with [¹¹C]raclopride and [¹¹C]FLB457. Psychopharmacology (Berl) 2012; 222:165-72. [PMID: 22237854 DOI: 10.1007/s00213-011-2633-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2011] [Accepted: 12/26/2011] [Indexed: 10/14/2022]
Abstract
RATIONALE Second-generation antipsychotics demonstrate clinical efficacy with fewer extrapyramidal side effects compared with first-generation antipsychotics. One of the proposed explanations is the hypothesis of preferential extrastriatal dopamine D₂ receptor occupancy (limbic selectivity) by antipsychotics. In the present study, we focused on aripiprazole, which has a unique pharmacological profile with partial agonism at dopamine D₂ receptors and the minimal risk of extrapyramidal side effects. Previous positron emission tomography (PET) studies using high-affinity radioligands for dopamine D₂ receptors have reported inconsistent results regarding regional differences of dopamine D₂ receptor occupancy by aripiprazole. OBJECTIVE To test the hypothesis of preferential binding to extrastriatal dopamine D₂ receptors by aripiprazole, we investigated its regional dopamine D₂ receptor occupancies in healthy young subjects. MATERIALS AND METHODS Using PET and two radioligands with different affinities for dopamine D₂ receptors, [¹¹C]raclopride and [¹¹C]FLB457, striatal and extrastriatal dopamine D₂ receptor bindings at baseline and after oral administration of 6 mg aripiprazole were measured in 11 male healthy subjects. RESULTS Our data showed that dopamine D₂ receptor occupancies in the striatum measured with [¹¹C]raclopride were 70.1% and 74.1%, with the corresponding values for the extrastriatal regions measured with [¹¹C]FLB457 ranging from 46.6% to 58.4%. CONCLUSIONS In the present study, preferential extrastriatal dopamine D₂ receptor occupancy by aripiprazole was not observed. Our data suggest partial agonism at dopamine D₂ receptors is the most likely explanation for the minimal risk of extrapyramidal side effects in the treatment by aripiprazole.
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Eisenstein SA, Koller JM, Piccirillo M, Kim A, Antenor-Dorsey JAV, Videen TO, Snyder AZ, Karimi M, Moerlein SM, Black KJ, Perlmutter JS, Hershey T. Characterization of extrastriatal D2 in vivo specific binding of [¹⁸F](N-methyl)benperidol using PET. Synapse 2012; 66:770-80. [PMID: 22535514 DOI: 10.1002/syn.21566] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Revised: 04/16/2012] [Accepted: 04/17/2012] [Indexed: 12/25/2022]
Abstract
PET imaging studies of the role of the dopamine D2 receptor family in movement and neuropsychiatric disorders are limited by the use of radioligands that have near-equal affinities for D2 and D3 receptor subtypes and are susceptible to competition with endogenous dopamine. By contrast, the radioligand [¹⁸F]N-methylbenperidol ([¹⁸F]NMB) has high selectivity and affinity for the D2 receptor subtype (D2R) and is not sensitive to endogenous dopamine. Although [¹⁸F]NMB has high binding levels in striatum, its utility for measuring D2R in extrastriatal regions is unknown. A composite MR-PET image was constructed across 14 healthy adult participants representing average NMB uptake 60 to 120 min after [¹⁸F]NMB injection. Regional peak radioactivity was identified using a peak-finding algorithm. FreeSurfer and manual tracing identified a priori regions of interest (ROI) on each individual's MR image and tissue activity curves were extracted from coregistered PET images. [¹⁸F]NMB binding potentials (BP(ND) s) were calculated using the Logan graphical method with cerebellum as reference region. In eight unique participants, extrastriatal BP(ND) estimates were compared between Logan graphical methods and a three-compartment kinetic tracer model. Radioactivity and BP(ND) levels were highest in striatum, lower in extrastriatal subcortical regions, and lowest in cortical regions relative to cerebellum. Age negatively correlated with striatal BP(ND) s. BP(ND) estimates for extrastriatal ROIs were highly correlated across kinetic and graphical methods. Our findings indicate that PET with [¹⁸F]NMB measures specific binding in extrastriatal regions, making it a viable radioligand to study extrastriatal D2R levels in healthy and diseased states.
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Affiliation(s)
- Sarah A Eisenstein
- Department of Psychiatry, Washington University School of Medicine in St. Louis, St. Louis, Missouri 63110, USA
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Muly EC, Votaw JR, Ritchie J, Howell LL. Relationship between dose, drug levels, and D2 receptor occupancy for the atypical antipsychotics risperidone and paliperidone. J Pharmacol Exp Ther 2012; 341:81-9. [PMID: 22214649 DOI: 10.1124/jpet.111.189076] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Blockade of D2 family dopamine receptors (D2Rs) is a fundamental property of antipsychotics, and the degree of striatal D2R occupancy has been related to antipsychotic and motor effects of these drugs. Recent studies suggest the D2R occupancy of antipsychotics may differ in extrastriatal regions compared with the dorsal striatum. We studied this issue in macaque monkeys by using a within-subjects design. [(18)F]fallypride positron emission tomography scans were obtained on four different doses of risperidone and paliperidone (the 9-OH metabolite of risperidone) and compared with multiple off-drug scans in each animal. The half-life of the two drugs in these monkeys was determined to be between 3 and 4 h, and drug was administered by a constant infusion through an intragastric catheter. The D2R occupancy of antipsychotic was determined in the caudate, putamen, ventral striatum, and four prefrontal and temporal cortical regions and was related to serum and cerebrospinal fluid drug levels. Repeated 2-week treatment with risperidone or paliperidone did not produce lasting changes in D2R binding potential in any region examined. As expected, D2R binding potential was highest in the caudate and putamen and was approximately one-third that level in the ventral striatum and 2% of that level in the cortical regions. We found dose-dependent D2R occupancy for both risperidone and paliperidone in both basal ganglia and cortical regions of interest. We could not find evidence of regional variation in D2R occupancy of either drug. Comparison of D2R occupancy and serum drug levels supports a target of 40 to 80 ng/ml active drug for these two atypical antipsychotics.
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Affiliation(s)
- E C Muly
- Atlanta Department of Veterans Affairs Medical Center, Decatur, Georgia, USA.
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Bernow N, Yakushev I, Landvogt C, Buchholz HG, Smolka MN, Bartenstein P, Lieb K, Gründer G, Vernaleken I, Schreckenberger M, Fehr C. Dopamine D2/D3 receptor availability and venturesomeness. Psychiatry Res 2011; 193:80-4. [PMID: 21689908 DOI: 10.1016/j.pscychresns.2011.01.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 12/01/2010] [Accepted: 01/13/2011] [Indexed: 10/18/2022]
Abstract
The construct of impulsivity is considered as a major trait of personality. There is growing evidence that the mesolimbic dopamine system plays an important role in the modulation of impulsivity and venturesomeness, the two key components within the impulsivity-construct. The aim of the present study was to explore an association between trait impulsivity measured with self-assessment and the dopaminergic neurotransmission as measured by positron emission tomography (PET) in a cohort of healthy male subjects. In vivo D2/D3 receptor availability was determined with [(18)F]fallypride PET in 18 non-smoking healthy subjects. The character trait impulsivity was measured using the Impulsiveness-Venturesomeness-Empathy questionnaire (I7). Image processing and statistical analysis was performed on a voxel-by-voxel basis using statistical parametric mapping (SPM) software. The I7 subscale venturesomeness correlated positively with the D2/D3 receptor availability within the left temporal cortex and the thalamus. Measures on the I7 subscale impulsiveness and empathy did not correlate with the D2/D3 receptor availability in any brain region investigated. Our results suggest the involvement of extrastriatal dopaminergic neurotransmission in venturesomeness, a component of impulsivity.
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Affiliation(s)
- Nina Bernow
- Department of Psychiatry and Psychotherapy, University of Mainz, Mainz, Germany
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Dopamine-mediated reinforcement learning signals in the striatum and ventromedial prefrontal cortex underlie value-based choices. J Neurosci 2011; 31:1606-13. [PMID: 21289169 DOI: 10.1523/jneurosci.3904-10.2011] [Citation(s) in RCA: 171] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A large body of evidence exists on the role of dopamine in reinforcement learning. Less is known about how dopamine shapes the relative impact of positive and negative outcomes to guide value-based choices. We combined administration of the dopamine D(2) receptor antagonist amisulpride with functional magnetic resonance imaging in healthy human volunteers. Amisulpride did not affect initial reinforcement learning. However, in a later transfer phase that involved novel choice situations requiring decisions between two symbols based on their previously learned values, amisulpride improved participants' ability to select the better of two highly rewarding options, while it had no effect on choices between two very poor options. During the learning phase, activity in the striatum encoded a reward prediction error. In the transfer phase, in the absence of any outcome, ventromedial prefrontal cortex (vmPFC) continually tracked the learned value of the available options on each trial. Both striatal prediction error coding and tracking of learned value in the vmPFC were predictive of subjects' choice performance in the transfer phase, and both were enhanced under amisulpride. These findings show that dopamine-dependent mechanisms enhance reinforcement learning signals in the striatum and sharpen representations of associative values in prefrontal cortex that are used to guide reinforcement-based decisions.
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XIIth international symposium on radiopharmaceutical chemistry: Abstracts and programme. J Labelled Comp Radiopharm 2010. [DOI: 10.1002/jlcr.2580400801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Esmaeilzadeh M, Farde L, Karlsson P, Varrone A, Halldin C, Waters S, Tedroff J. Extrastriatal dopamine D(2) receptor binding in Huntington's disease. Hum Brain Mapp 2010; 32:1626-36. [PMID: 20886576 DOI: 10.1002/hbm.21134] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 06/06/2010] [Accepted: 06/28/2010] [Indexed: 12/13/2022] Open
Abstract
Huntington's disease (HD) is a neurodegenerative disorder, primarily affecting medium spiny neurones in the striatum. The density of striatal dopamine D(2) receptors is reduced in HD but there is little known about this biomarker in brain regions outside the striatum. The primary objective of this study was to compare extrastriatal dopamine D(2) receptor binding, in age-matched control subjects and patients with HD. All subjects were examined using a high-resolution positron emission tomography system and the high-affinity dopamine D(2) receptor radioligand [(11) C]FLB 457. A ROI based analysis was used with an atrophy correction method. Dopamine D(2) receptor binding potential was reduced in the striatum of patients with HD. Unlike the striatum, dopamine D(2) receptor binding in thalamic and cortical subregions was not significantly different from that in control subjects. A partial least square regression analysis which included binding potential values from all investigated cortical and subcortical regions revealed a significant model separating patients from controls, conclusively dependent on differences in striatal binding of the radioligand. Some clinical assessments correlated with striatal dopamine D(2) receptor binding, including severity of chorea and cognitive test performance. Hence, the present study demonstrates that dopamine D(2) receptors extrinsic to the striatum are well preserved in early to mid stage patients with HD. This observation may have implication for the development of therapy for HD.
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Affiliation(s)
- Mouna Esmaeilzadeh
- PET Centre, Stockholm Brain Institute, Karolinska Institutet, Stockholm, Sweden.
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Tuppurainen H, Kuikka JT, Viinamäki H, Husso M, Tiihonen J. Extrapyramidal side-effects and dopamine D(2/3) receptor binding in substantia nigra. Nord J Psychiatry 2010; 64:233-8. [PMID: 20629610 DOI: 10.3109/08039480903484076] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND The exact mechanisms for antipsychotic-induced extrapyramidal side-effects have remained obscure despite intensive research. Previous studies have highlighted a central role for nigral dopamine D(2) receptors in the control of motor functions. AIMS The aim of the present study was to examine relationships between dopamine D(2) receptor binding in both substantia nigra and temporal cortex with extrapyramidal symptoms among antipsychotic-treated patients with schizophrenia. METHODS Single-photon emission-computed tomography (SPECT) ligand [(123)I]epidepride was used to determine dopamine D(2/3) apparent binding potential in 13 antipsychotic-treated (seven with clozapine, four with olanzapine and two with haloperidol) patients with schizophrenia. Extrapyramidal symptoms were assessed with the Simpson and Angus Scale (SAS). RESULTS A statistically significant correlation was observed between dopamine D(2/3) receptor apparent binding potential in the substantia nigra and extrapyramidal side-effects (r = -0.62, P = 0.024). No correlations were detected in the temporal cortex between dopamine D(2/3) receptor binding and extrapyramidal side-effects. CONCLUSIONS These findings support the role of dopamine D(2) autoreceptors in substantia nigra regarding drug-induced movement disorders.
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Affiliation(s)
- Heli Tuppurainen
- Department of Forensic Psychiatry, University of Kuopio, Niuvanniemi Hospital, FI-70240 Kuopio, Finland.
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Cervenka S, Varrone A, Fransén E, Halldin C, Farde L. PET studies of D2-receptor binding in striatal and extrastriatal brain regions: Biochemical support in vivo for separate dopaminergic systems in humans. Synapse 2010; 64:478-85. [PMID: 20175222 DOI: 10.1002/syn.20765] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Most molecular imaging studies of the dopamine (DA) system performed to date have focused on the striatum, a region receiving dense dopaminergic innervation. In clinical research on the DA D2-receptor, striatal binding has often been regarded as an index of global DA function, based on the underlying assumption of common regulatory mechanisms for receptor expression across brain regions. Recent data has challenged this view, suggesting differences in genetic regulation between striatal and extrastriatal brain regions. The relationship between binding levels in brain regions has, however, not been directly examined in the same sample. In this study, we searched for interregional correlations between DA D2-receptor availability as determined with Positron Emission Tomography in 16 control subjects. The radioligands [11C]raclopride and [11C]FLB 457 were used for measurements of D2-receptor binding in striatal and extrastriatal regions, respectively. No correlation was observed between D2-receptor availability in striatum and any of the extrastriatal regions, as assessed using both region of interest- and voxel-based analyses. Instead, the pattern of correlations was consistent with the model of separate dopaminergic systems as has been originally observed in rodents. These preliminary results encourage approaches searching for individual patterns of receptor binding across the whole brain volume in clinical studies on the dopamine system.
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Affiliation(s)
- Simon Cervenka
- Department of Clinical Neuroscience, Stockholm Brain Institute/Karolinska Institute, Stockholm, Sweden.
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de Manzano O, Cervenka S, Karabanov A, Farde L, Ullén F. Thinking outside a less intact box: thalamic dopamine D2 receptor densities are negatively related to psychometric creativity in healthy individuals. PLoS One 2010; 5:e10670. [PMID: 20498850 PMCID: PMC2871784 DOI: 10.1371/journal.pone.0010670] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2010] [Accepted: 04/11/2010] [Indexed: 11/29/2022] Open
Abstract
Several lines of evidence support that dopaminergic neurotransmission plays a role in creative thought and behavior. Here, we investigated the relationship between creative ability and dopamine D2 receptor expression in healthy individuals, with a focus on regions where aberrations in dopaminergic function have previously been associated with psychotic symptoms and a genetic liability to schizophrenia. Scores on divergent thinking tests (Inventiveness battery, Berliner Intelligenz Struktur Test) were correlated with regional D2 receptor densities, as measured by Positron Emission Tomography, and the radioligands [11C]raclopride and [11C]FLB 457. The results show a negative correlation between divergent thinking scores and D2 density in the thalamus, also when controlling for age and general cognitive ability. Hence, the results demonstrate that the D2 receptor system, and specifically thalamic function, is important for creative performance, and may be one crucial link between creativity and psychopathology. We suggest that decreased D2 receptor densities in the thalamus lower thalamic gating thresholds, thus increasing thalamocortical information flow. In healthy individuals, who do not suffer from the detrimental effects of psychiatric disease, this may increase performance on divergent thinking tests. In combination with the cognitive functions of higher order cortical networks, this could constitute a basis for the generative and selective processes that underlie real life creativity.
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Affiliation(s)
- Orjan de Manzano
- Neuropediatric Research Unit, Department of Women's and Children's Health and Stockholm Brain Institute, Karolinska Institutet, Stockholm, Sweden.
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Zald DH, Woodward ND, Cowan RL, Riccardi P, Ansari MS, Baldwin RM, Cowan RL, Smith CE, Hakyemez H, Li R, Kessler RM. The interrelationship of dopamine D2-like receptor availability in striatal and extrastriatal brain regions in healthy humans: a principal component analysis of [18F]fallypride binding. Neuroimage 2010; 51:53-62. [PMID: 20149883 DOI: 10.1016/j.neuroimage.2010.02.006] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Revised: 01/31/2010] [Accepted: 02/03/2010] [Indexed: 11/27/2022] Open
Abstract
Individual differences in dopamine D2-like receptor availability arise across all brain regions expressing D2-like receptors. However, the interrelationships in receptor availability across brain regions are poorly understood. To address this issue, we examined the relationship between D2-like binding potential (BPND) across striatal and extrastriatal regions in a sample of healthy participants. PET imaging was performed with the high affinity D2/D3 ligand [18F]fallypride in 45 participants. BPND images were submitted to voxel-wise principal component analysis to determine the pattern of associations across brain regions. Individual differences in D2-like BPND were explained by three distinguishable components. A single component explained almost all of the variance within the striatum, indicating that individual differences in receptor availability vary in a homogenous manner across the caudate, putamen, and ventral striatum. Cortical BPND was only modestly related to striatal BPND and mostly loaded on a distinct component. After controlling for the general level of cortical D2-like BPND, an inverse relationship emerged between receptor availability in the striatum and the ventral temporal and ventromedial frontal cortices, suggesting possible cross-regulation of D2-like receptors in these regions. The analysis additionally revealed evidence of: (1) a distinct component involving the midbrain and limbic areas; (2) a dissociation between BPND in the medial and lateral temporal regions; and (3) a dissociation between BPND in the medial/midline and lateral thalamus. In summary, individual differences in D2-like receptor availability reflect several distinct patterns. This conclusion has significant implications for neuropsychiatric models that posit global or regionally specific relationships between dopaminergic tone and behavior.
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Affiliation(s)
- David H Zald
- Department of Psychology, Vanderbilt University, 325 Wilson Hall, 111 21st Ave. South, Nashville, TN 37212, USA.
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Hirvonen MM, Någren K, Rinne JO, Pesonen U, Vahlberg T, Hagelberg N, Hietala J. COMT Val158Met genotype does not alter cortical or striatal dopamine D2 receptor availability in vivo. Mol Imaging Biol 2009; 12:192-7. [PMID: 19795175 DOI: 10.1007/s11307-009-0257-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2009] [Accepted: 05/04/2009] [Indexed: 10/20/2022]
Abstract
PURPOSE Catechol-O-methyl transferase (COMT) is a pivotal regulator of brain dopamine function with a region-specific role. COMT is important in dopamine elimination in the prefrontal cortex, whereas dopamine reuptake is the main mechanism for synaptic removal of dopamine in the striatum. We studied whether the functional COMT gene polymorphism (Val158Met) associates with altered dopamine D2 receptor binding characteristics in vivo hypothesizing an effect in the cortex but not in the striatum. PROCEDURES Samples of 38 and 45 Finnish healthy subjects scanned previously with PET and the D2/D3 receptor radioligands [(11)C]FLB457 or [(11)C]raclopride, respectively, were genotyped for the Val158Met polymorphism. RESULTS No significant associations were found between the Val158Met genotype and D2 receptor binding characteristics in the cortex or the striatum as measured with [(11)C]FLB457 and [(11)C]raclopride, respectively. CONCLUSIONS COMT genotype is not related with alterations in baseline D2 receptor availability in vivo in the cortex or the striatum. This information is useful for the interpretation of genetic studies on COMT in neuropsychiatry.
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Affiliation(s)
- Mika M Hirvonen
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Turku, Finland
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Tuppurainen H, Kuikka JT, Viinamäki H, Husso M, Tiihonen J. Dopamine D2/3 receptor binding potential and occupancy in midbrain and temporal cortex by haloperidol, olanzapine and clozapine. Psychiatry Clin Neurosci 2009; 63:529-37. [PMID: 19496999 DOI: 10.1111/j.1440-1819.2009.01982.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
AIMS Aberrant dopamine transmission in extrastriatal brain regions has been repeatedly illustrated among patients with schizophrenia. Differences between typical and second-generation antipsychotics in dopamine D(2) receptor modulation within various brain areas remain a topic for debate. The aim of the present study was therefore to investigate dopamine D(2/3) receptor apparent binding potential (BP(app)) and occupancy in midbrain and temporal cortex among clozapine-, olanzapine- and haloperidol-treated schizophrenia patients. METHODS Dopamine D(2/3) binding was studied on single-photon emission computed tomography ligand [(123)I]epidepride in 13 schizophrenia patients treated with medication (two with haloperidol, four with olanzapine and seven with clozapine), six drug-naïve patients and seven healthy controls. RESULTS Statistically significant differences in midbrain dopamine D(2/3) receptor BP(app) (P = 0.015) and occupancy (P = 0.016) were observed between the clozapine, olanzapine and haloperidol groups. The lowest occupancy was found in clozapine-treated patients (5%), followed by olanzapine-treated patients (28%), compared to haloperidol-treated patients (40%). No significant differences were observed in the temporal poles. Occupancy changed substantially depending on the comparison group used (either drug-naïve vs healthy controls) in the examined brain areas (P = 0.001), showing an overestimation with all antipsychotics when the healthy control group was used. CONCLUSION Both typical and second-generation antipsychotics occupy cortical dopamine D(2/3) receptors, thus mediating therapeutic efficacy. Observed differences in midbrain dopamine D(2/3) occupancy between classical antipsychotics and second-generation antipsychotics may have clinical relevance by modulating altered nigrostriatal dopamine neurotransmission during the acute phase of schizophrenia.
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Affiliation(s)
- Heli Tuppurainen
- Department of Forensic Psychiatry, University of Kuopio, Niuvanniemi Hospital, Kuopio, Finland.
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Narendran R, Frankle WG, Mason NS, Rabiner EA, Gunn RN, Searle GE, Vora S, Litschge M, Kendro S, Cooper TB, Mathis CA, Laruelle M. Positron emission tomography imaging of amphetamine-induced dopamine release in the human cortex: a comparative evaluation of the high affinity dopamine D2/3 radiotracers [11C]FLB 457 and [11C]fallypride. Synapse 2009; 63:447-61. [PMID: 19217025 DOI: 10.1002/syn.20628] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The use of PET and SPECT endogenous competition binding techniques has contributed to the understanding of the role of dopamine in several neuropsychiatric disorders. An important limitation of these imaging studies is the fact that measurements of acute changes in synaptic dopamine have been restricted to the striatum. The ligands previously used, such as [(11)C]raclopride and [(123)I]IBZM, do not provide sufficient signal to noise ratio to quantify D(2) receptors in extrastriatal areas, such as cortex, where the concentration of D(2) receptors is much lower than in the striatum. Given the importance of cortical DA function in cognition, a method to measure cortical dopamine function in humans would be highly desirable. The goal of this study was to compare the ability of two high affinity DA D(2) radioligands [(11)C]FLB 457 and [(11)C]fallypride to measure amphetamine-induced changes in DA transmission in the human cortex. D(2) receptor availability was measured in the cortical regions of interest with PET in 12 healthy volunteers under control and postamphetamine conditions (0.5 mg kg(-1), oral), using both [(11)C]FLB 457 and [(11)C]fallypride (four scans per subjects). Kinetic modeling with an arterial input function was used to derive the binding potential (BP(ND)) in eight cortical regions. Under controlled conditions, [(11)C]FLB 457 BP(ND) was 30-70% higher compared with [(11)C]fallypride BP(ND) in cortical regions. Amphetamine induced DA release led to a significant decrease in [(11)C]FLB 457 BP(ND) in five out the eight cortical regions evaluated. In contrast, no significant decrease in [(11)C]fallypride BP(ND) was detected in cortex following amphetamine. The difference between [(11)C]FLB 457 and [(11)C]fallypride ability to detect changes in the cortical D(2) receptor availability following amphetamine is related to the higher signal to noise ratio provided by [(11)C]FLB 457. These findings suggest that [(11)C]FLB 457 is superior to [(11)C]fallypride for measurement of changes in cortical synaptic dopamine.
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Affiliation(s)
- Rajesh Narendran
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA.
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Hirvonen MM, Lumme V, Hirvonen J, Pesonen U, Någren K, Vahlberg T, Scheinin H, Hietala J. C957T polymorphism of the human dopamine D2 receptor gene predicts extrastriatal dopamine receptor availability in vivo. Prog Neuropsychopharmacol Biol Psychiatry 2009; 33:630-6. [PMID: 19285111 DOI: 10.1016/j.pnpbp.2009.02.021] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Revised: 02/27/2009] [Accepted: 02/27/2009] [Indexed: 11/24/2022]
Abstract
The C957T (rs6277) single nucleotide polymorphism (SNP) of the human dopamine D2 receptor (DRD2) gene (DRD2) affects DRD2 mRNA stability and has been shown to predict striatal DRD2 availability (B(max)/K(D)) in vivo in man. Specifically, the C/C genotype is associated with low striatal DRD2 availability (C/C<C/T<T/T). It is not known, however, whether this pattern of genetic regulation of DRD2 expression also applies to low density DRD2 populations in extrastriatal regions. We analyzed extrastriatal DRD2 availability (indexed by binding potential, BP(ND)) measured in 38 healthy male volunteers with 3D-PET and the high-affinity DRD2 radioligand [(11)C]FLB457. The subjects were genotyped for the C957T as well as for two other widely studied DRD2 SNPs, the TaqIA (rs1800497) and the -141C Ins/Del (rs1799732). Statistical analyses showed that the C957T C/C genotype was associated with high extrastriatal DRD2 BP(ND) throughout the cortex and the thalamus (C/C>C/T>T/T). Also the TaqIA A1 allele carriers (p=0.101) tended to have higher extrastriatal DRD2 BP(ND) compared to non-carriers whereas the -141C Ins/Del genotype did not influence extrastriatal DRD2 BP(ND). Our findings indicate that the DRD2 SNPs regulate DRD2 availability in the human cortex and in the thalamus in vivo. However, the regulation pattern is different from that observed previously for striatal DRD2 availability in vivo, which may reflect distinct functional roles of dopamine and DRD2 in the cortex versus the striatum. The results provide useful information for the interpretation of genetic studies exploring the role of the DRD2 in normal physiology as well as in psychiatric and neurological diseases.
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Affiliation(s)
- Mika M Hirvonen
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, 20014 Turku, Finland
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Seneca N, Zoghbi SS, Skinbjerg M, Liow JS, Hong J, Sibley DR, Pike VW, Halldin C, Innis RB. Occupancy of dopamine D2/3 receptors in rat brain by endogenous dopamine measured with the agonist positron emission tomography radioligand [11C]MNPA. Synapse 2009; 62:756-63. [PMID: 18651641 DOI: 10.1002/syn.20549] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Estimates of dopamine D(2/3) receptor occupancy by endogenous dopamine using positron emission tomography (PET) in animals have varied almost threefold. This variability may have been caused by incomplete depletion of dopamine or by the use of antagonist radioligands, which appear less sensitive than agonist radioligands to changes in endogenous dopamine. PET scans were performed in rats with the agonist PET radioligand [(11)C]MNPA ([O-methyl-(11)C]2-methoxy-N-propylnorapomorphine). [(11)C]MNPA was injected as a bolus plus constant infusion to achieve steady-state concentration in the body and equilibrium receptor binding in the brain. Radioligand binding was compared at baseline and after treatment with reserpine plus alpha-methyl-para-tyrosine, which cause approximately 95% depletion of endogenous dopamine. Depletion of dopamine increased radioligand binding in striatum but had little effect in cerebellum. Striatal [(11)C]MNPA binding potential was 0.93 +/- 0.12 at baseline and increased to 1.99 +/- 0.25 after dopamine depletion. Occupancy of D(2/3) receptors by endogenous dopamine at baseline was calculated to be approximately 53%. Striatal binding was displaceable with raclopride, but not with BP 897 (a selective D(3) compound), thus confirming the D(2) receptor specificity of [(11)C]MNPA binding. Radioactivity extracted from rat brain contained only 8-10% radiometabolites and was insignificantly altered by administration of reserpine plus alpha-methyl-para-tyrosine. Hence, dopamine depletion did not increase the PET measurements via an effect on radiotracer metabolism. Our in vivo estimate of dopamine's occupancy of D(2/3) receptors at baseline is higher than that previously reported using antagonist radioligands and PET, but is similar to that reported using agonist radioligands and ex vivo measurements.
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Affiliation(s)
- Nicholas Seneca
- Molecular Imaging Branch, National Institute of Mental Health, Bethesda, Maryland 20892-2035, USA.
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Aalto S, Hirvonen J, Kaasinen V, Hagelberg N, Kajander J, Någren K, Seppälä T, Rinne JO, Scheinin H, Hietala J. The effects of d-amphetamine on extrastriatal dopamine D2/D3 receptors: a randomized, double-blind, placebo-controlled PET study with [11C]FLB 457 in healthy subjects. Eur J Nucl Med Mol Imaging 2008; 36:475-83. [DOI: 10.1007/s00259-008-0969-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2008] [Accepted: 09/15/2008] [Indexed: 10/21/2022]
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