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Versteeg RI, Schrantee A, Adriaanse SM, Unmehopa UA, Booij J, Reneman L, Fliers E, Fleur SE, Serlie MJ. Timing of caloric intake during weight loss differentially affects striatal dopamine transporter and thalamic serotonin transporter binding. FASEB J 2017; 31:4545-4554. [DOI: 10.1096/fj.201601234r] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2016] [Accepted: 06/19/2017] [Indexed: 01/10/2023]
Affiliation(s)
- Ruth I. Versteeg
- Department of Endocrinology and MetabolismUniversity of AmsterdamAmsterdamThe Netherlands
| | - Anouk Schrantee
- Department of RadiologyUniversity of AmsterdamAmsterdamThe Netherlands
| | - Sofie M. Adriaanse
- Department of Nuclear MedicineAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Unga A. Unmehopa
- Department of Endocrinology and MetabolismUniversity of AmsterdamAmsterdamThe Netherlands
| | - Jan Booij
- Department of Nuclear MedicineAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Liesbeth Reneman
- Department of RadiologyUniversity of AmsterdamAmsterdamThe Netherlands
| | - Eric Fliers
- Department of Endocrinology and MetabolismUniversity of AmsterdamAmsterdamThe Netherlands
| | - Susanne E. Fleur
- Department of Endocrinology and MetabolismUniversity of AmsterdamAmsterdamThe Netherlands
| | - Mireille J. Serlie
- Department of Endocrinology and MetabolismUniversity of AmsterdamAmsterdamThe Netherlands
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Schrantee A, Václavů L, Reneman L, Verberne HJ, Booij J, Tan HL. QT prolongation by dexamphetamine: Does experience matter? J Cardiovasc Electrophysiol 2017; 28:912-916. [PMID: 28452189 DOI: 10.1111/jce.13235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 03/23/2017] [Accepted: 04/12/2017] [Indexed: 12/01/2022]
Abstract
INTRODUCTION Case reports of life-threatening cardiac arrhythmias and sudden cardiac arrest (SCA) among amphetamine users have raised serious concerns about the cardiac safety of this class of drugs. This is important in light of the high prevalence of dexamphetamine (dAMPH) prescription for attention-deficit/hyperactivity disorder (ADHD), and its rising use as a recreational drug. The objective was to investigate electrocardiogram (ECG) parameters upon intravenous administration of a single dAMPH dose in habitual recreational dAMPH users (users) and healthy gender/age/ intelligence-quotient-matched controls (non-users). METHODS AND RESULTS ECG recordings were made in 18 users and 18 non-users during administration of dAMPH (0.3 mg/kg body weight). Baseline ECG was normal in both groups. dAMPH elicited increased heart rate and corrected QT time (QTc) prolongation in both groups (all P < 0.001, QTc = 502 in one individual). QTc prolongation was attenuated in users compared to non-users, exhibiting a significant interaction effect (P = 0.04). CONCLUSION SCA associated with amphetamine use may be related to its QTc prolonging effects, particularly during first-time use. These observations may provide a rationale for conducting ECG analysis immediately after the first-time use of amphetamines, as this could potentially unmask vulnerable individuals.
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Affiliation(s)
- Anouk Schrantee
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Lena Václavů
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Liesbeth Reneman
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Hein J Verberne
- Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Jan Booij
- Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Hanno L Tan
- Department of Cardiology, Heart Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Schrantee A, Tremoleda JL, Wylezinska-Arridge M, Bouet V, Hesseling P, Meerhoff GF, de Bruin KM, Koeleman J, Freret T, Boulouard M, Desfosses E, Galineau L, Gozzi A, Dauphin F, Gsell W, Booij J, Lucassen PJ, Reneman L. Repeated dexamphetamine treatment alters the dopaminergic system and increases the phMRI response to methylphenidate. PLoS One 2017; 12:e0172776. [PMID: 28241065 PMCID: PMC5328278 DOI: 10.1371/journal.pone.0172776] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 02/09/2017] [Indexed: 12/12/2022] Open
Abstract
Dexamphetamine (AMPH) is a psychostimulant drug that is used both recreationally and as medication for attention deficit hyperactivity disorder. Preclinical studies have demonstrated that repeated exposure to AMPH can induce damage to nerve terminals of dopamine (DA) neurons. We here assessed the underlying neurobiological changes in the DA system following repeated AMPH exposure and pre-treated rats with AMPH or saline (4 times 5 mg/kg s.c., 2 hours apart), followed by a 1-week washout period. We then used pharmacological MRI (phMRI) with a methylphenidate (MPH) challenge, as a sensitive and non-invasive in-vivo measure of DAergic function. We subsequently validated the DA-ergic changes post-mortem, using a.o. high-performance liquid chromatography (HPLC) and autoradiography. In the AMPH pre-treated group, we observed a significantly larger BOLD response to the MPH challenge, particularly in DA-ergic brain areas and their downstream projections. Subsequent autoradiography studies showed that AMPH pre-treatment significantly reduced DA transporter (DAT) density in the caudate-putamen (CPu) and nucleus accumbens, whereas HPLC analysis revealed increases in the DA metabolite homovanillic acid in the CPu. Our results suggest that AMPH pre-treatment alters DAergic responsivity, a change that can be detected with phMRI in rats. These phMRI changes likely reflect increased DA release together with reduced DAT binding. The ability to assess subtle synaptic changes using phMRI is promising for both preclinical studies of drug discovery, and for clinical studies where phMRI can be a useful tool to non-invasively investigate DA abnormalities, e.g. in neuropsychiatric disorders.
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Affiliation(s)
- Anouk Schrantee
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Biological Imaging Centre, Imperial College London, White City, London, United Kingdom
- * E-mail:
| | - Jordi L. Tremoleda
- Biological Imaging Centre, Imperial College London, White City, London, United Kingdom
- Centre for Trauma Sciences, The Blizard Institute, London, United Kingdom
| | - Marzena Wylezinska-Arridge
- Biological Imaging Centre, Imperial College London, White City, London, United Kingdom
- Neuroradiological Academic Unit, Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, Queen Square, London, United Kingdom
| | - Valentine Bouet
- Normandie-Université, GMPc, EA 4259, Université de Caen Basse-Normandie, Caen, France
| | - Peter Hesseling
- Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, The Netherlands
| | - Gideon F. Meerhoff
- Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, The Netherlands
| | - Kora M. de Bruin
- Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Jan Koeleman
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Thomas Freret
- Normandie-Université, GMPc, EA 4259, Université de Caen Basse-Normandie, Caen, France
| | - Michel Boulouard
- Normandie-Université, GMPc, EA 4259, Université de Caen Basse-Normandie, Caen, France
| | - Emilie Desfosses
- UMR Inserm U930, Université François-Rabelais de Tours, Tours, France
| | - Laurent Galineau
- UMR Inserm U930, Université François-Rabelais de Tours, Tours, France
| | - Alessandro Gozzi
- Functional Neuroimaging Laboratory, Istituto Italiano di Tecnologia, Center for Neuroscience and Cognitive Systems @ UNITN, Rovereto, Italy
| | - François Dauphin
- Normandie-Université, GMPc, EA 4259, Université de Caen Basse-Normandie, Caen, France
| | - Willy Gsell
- Biological Imaging Centre, Imperial College London, White City, London, United Kingdom
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium
| | - Jan Booij
- Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Paul J. Lucassen
- Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, The Netherlands
| | - Liesbeth Reneman
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Schrantee A, Mutsaerts HJMM, Bouziane C, Tamminga HGH, Bottelier MA, Reneman L. The age-dependent effects of a single-dose methylphenidate challenge on cerebral perfusion in patients with attention-deficit/hyperactivity disorder. Neuroimage Clin 2016; 13:123-129. [PMID: 27942455 PMCID: PMC5137172 DOI: 10.1016/j.nicl.2016.11.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 11/18/2016] [Accepted: 11/19/2016] [Indexed: 10/26/2022]
Abstract
Methylphenidate (MPH) is a stimulant drug and an effective treatment for attention-deficit/hyperactivity disorder (ADHD) in both children and adults. Pre-clinical studies suggest that the response to stimulants is dependent on age, which may reflect the ontogeny of the dopamine (DA) system, which continues to develop throughout childhood and adolescence. Therefore, the aim of this study was to investigate the modulating effect of age on the cerebral blood flow (CBF) response to MPH in stimulant treatment-naive children and adults with ADHD. Ninety-eight stimulant treatment-naive male pediatric (10-12 years) and adult (23-40 years) patients with ADHD were included in this study. The CBF response to an acute challenge with MPH (0.5 mg/kg) was measured using arterial spin labeling (ASL) pharmacological magnetic resonance imaging, as a proxy for DA function. Region-of-interest (ROI) analyses were carried out for the striatum, thalamus and medial prefrontal cortex and in addition voxel-wise analyses were conducted. An acute challenge with MPH decreased CBF in both children and adults in cortical areas, although to a greater extent in adults. In contrast, ROI analyses showed that MPH decreased thalamic CBF only in children, but not adults. Our findings highlight the importance of taking the developmental perspective into account when studying the effects of stimulants in ADHD patients.
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Affiliation(s)
- A Schrantee
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Amsterdam Brain and Cognition, University of Amsterdam, Amsterdam, The Netherlands
| | - HJMM Mutsaerts
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Sunnybrook Research Institute, University of Toronto, Toronto, ON, Canada
| | - C Bouziane
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - HGH Tamminga
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands
| | - MA Bottelier
- Department of Child- and Adolescent Psychiatry, Triversum, Alkmaar, The Netherlands
| | - L Reneman
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Amsterdam Brain and Cognition, University of Amsterdam, Amsterdam, The Netherlands
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Schrantee A, Tamminga HGH, Bouziane C, Bottelier MA, Bron EE, Mutsaerts HJMM, Zwinderman AH, Groote IR, Rombouts SARB, Lindauer RJL, Klein S, Niessen WJ, Opmeer BC, Boer F, Lucassen PJ, Andersen SL, Geurts HM, Reneman L. Age-Dependent Effects of Methylphenidate on the Human Dopaminergic System in Young vs Adult Patients With Attention-Deficit/Hyperactivity Disorder: A Randomized Clinical Trial. JAMA Psychiatry 2016; 73:955-62. [PMID: 27487479 PMCID: PMC5267166 DOI: 10.1001/jamapsychiatry.2016.1572] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
IMPORTANCE Although numerous children receive methylphenidate hydrochloride for the treatment of attention-deficit/hyperactivity disorder (ADHD), little is known about age-dependent and possibly lasting effects of methylphenidate on the human dopaminergic system. OBJECTIVES To determine whether the effects of methylphenidate on the dopaminergic system are modified by age and to test the hypothesis that methylphenidate treatment of young but not adult patients with ADHD induces lasting effects on the cerebral blood flow response to dopamine challenge, a noninvasive probe for dopamine function. DESIGN, SETTING, AND PARTICIPANTS A randomized, double-blind, placebo-controlled trial (Effects of Psychotropic Drugs on Developing Brain-Methylphenidate) among ADHD referral centers in the greater Amsterdam area in the Netherlands between June 1, 2011, and June 15, 2015. Additional inclusion criteria were male sex, age 10 to 12 years or 23 to 40 years, and stimulant treatment-naive status. INTERVENTIONS Treatment with either methylphenidate or a matched placebo for 16 weeks. MAIN OUTCOMES AND MEASURES Change in the cerebral blood flow response to an acute challenge with methylphenidate, noninvasively assessed using pharmacological magnetic resonance imaging, between baseline and 1 week after treatment. Data were analyzed using intent-to-treat analyses. RESULTS Among 131 individuals screened for eligibility, 99 patients met DSM-IV criteria for ADHD, and 50 participants were randomized to receive methylphenidate and 49 to placebo. Sixteen weeks of methylphenidate treatment increased the cerebral blood flow response to methylphenidate within the thalamus (mean difference, 6.5; 95% CI, 0.4-12.6; P = .04) of children aged 10 to 12 years old but not in adults or in the placebo group. In the striatum, the methylphenidate condition differed significantly from placebo in children but not in adults (mean difference, 7.7; 95% CI, 0.7-14.8; P = .03). CONCLUSIONS AND RELEVANCE We confirm preclinical data and demonstrate age-dependent effects of methylphenidate treatment on human extracellular dopamine striatal-thalamic circuitry. Given its societal relevance, these data warrant replication in larger groups with longer follow-up. TRIAL REGISTRATION identifier: NL34509.000.10 and trialregister.nl identifier: NTR3103.
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Affiliation(s)
- Anouk Schrantee
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands2Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands3Amsterdam Brain and Cognition, University of Amsterdam, Amsterdam, the Netherlands
| | - Hyke G. H. Tamminga
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands4d’Arc (Dutch Autism and Attention-Deficit/Hyperactivity Disorder Research Center), Department of Brain and Cognition, University of Amsterdam, Amsterdam, the Netherlands
| | - Cheima Bouziane
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands2Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Marco A. Bottelier
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands5Department of Child and Adolescent Psychiatry, Triversum, Alkmaar, the Netherlands
| | - Esther E. Bron
- Biomedical Imaging Group Rotterdam, Department of Medical Informatics, Erasmus Medical Center, Rotterdam, the Netherlands7Biomedical Imaging Group Rotterdam, Department of Radiology, Erasmus MC, Rotterdam, the Netherlands
| | - Henk-Jan M. M. Mutsaerts
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands2Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Aeilko H. Zwinderman
- Department of Clinical Epidemiology and Biostatistics, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Inge R. Groote
- Institute of Psychology, Department of Social Sciences, University of Oslo, Oslo, Norway
| | - Serge A. R. B. Rombouts
- Institute of Psychology, Leiden University, Leiden, the Netherlands11Department of Radiology, Leids Universitair Medisch Centrum, Leiden, the Netherlands
| | - Ramon J. L. Lindauer
- Department of Child and Adolescent Psychiatry, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands13De Bascule Academic Center for Child and Adolescent Psychiatry, Amsterdam, the Netherlands
| | - Stefan Klein
- Biomedical Imaging Group Rotterdam, Department of Medical Informatics, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Wiro J. Niessen
- Biomedical Imaging Group Rotterdam, Department of Medical Informatics, Erasmus Medical Center, Rotterdam, the Netherlands14Department of Imaging Physics, Faculty of Applied Sciences, Delft University of Technology, Delft, the Netherlands
| | - Brent C. Opmeer
- Clinical Research Unit, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Frits Boer
- Department of Child and Adolescent Psychiatry, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands13De Bascule Academic Center for Child and Adolescent Psychiatry, Amsterdam, the Netherlands
| | - Paul J. Lucassen
- Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, the Netherlands
| | - Susan L. Andersen
- Department of Psychiatry, Harvard Medical School and McLean Hospital, Belmont, Massachusetts
| | - Hilde M. Geurts
- d’Arc (Dutch Autism and Attention-Deficit/Hyperactivity Disorder Research Center), Department of Brain and Cognition, University of Amsterdam, Amsterdam, the Netherlands
| | - Liesbeth Reneman
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands2Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands3Amsterdam Brain and Cognition, University of Amsterdam, Amsterdam, the Netherlands
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Perkins AM, Ettinger U, Weaver K, Schmechtig A, Schrantee A, Morrison PD, Sapara A, Kumari V, Williams SCR, Corr PJ. Advancing the defensive explanation for anxiety disorders: lorazepam effects on human defense are systematically modulated by personality and threat-type. Transl Psychiatry 2013; 3:e246. [PMID: 23591970 PMCID: PMC3641407 DOI: 10.1038/tp.2013.20] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 02/04/2013] [Accepted: 02/18/2013] [Indexed: 11/09/2022] Open
Abstract
Clinically effective drugs against human anxiety and fear systematically alter the innate defensive behavior of rodents, suggesting that in humans these emotions reflect defensive adaptations. Compelling experimental human evidence for this theory is yet to be obtained. We report the clearest test to date by investigating the effects of 1 and 2 mg of the anti-anxiety drug lorazepam on the intensity of threat-avoidance behavior in 40 healthy adult volunteers (20 females). We found lorazepam modulated the intensity of participants' threat-avoidance behavior in a dose-dependent manner. However, the pattern of effects depended upon two factors: type of threat-avoidance behavior and theoretically relevant measures of personality. In the case of flight behavior (one-way active avoidance), lorazepam increased intensity in low scorers on the Fear Survey Schedule tissue-damage fear but reduced it in high scorers. Conversely, in the case of risk-assessment behavior (two-way active avoidance), lorazepam reduced intensity in low scorers on the Spielberger trait anxiety but increased it in high scorers. Anti-anxiety drugs do not systematically affect rodent flight behavior; therefore, we interpret this new finding as suggesting that lorazepam has a broader effect on defense in humans than in rodents, perhaps by modulating general perceptions of threat intensity. The different patterning of lorazepam effects on the two behaviors implies that human perceptions of threat intensity are nevertheless distributed across two different neural streams, which influence effects observed on one-way or two-way active avoidance demanded by the situation.
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Affiliation(s)
- A M Perkins
- King's College London, Department of Psychological Medicine, Institute of Psychiatry, London, UK.
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Klomp A, Tremoleda JL, Schrantee A, Gsell W, Reneman L. The use of pharmacological-challenge fMRI in pre-clinical research: application to the 5-HT system. J Vis Exp 2012:3956. [PMID: 22565099 PMCID: PMC3466645 DOI: 10.3791/3956] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Pharmacological MRI (phMRI) is a new and promising method to study the effects of substances on brain function that can ultimately be used to unravel underlying neurobiological mechanisms behind drug action and neurotransmitter-related disorders, such as depression and ADHD. Like most of the imaging methods (PET, SPECT, CT) it represents a progress in the investigation of brain disorders and the related function of neurotransmitter pathways in a non-invasive way with respect of the overall neuronal connectivity. Moreover it also provides the ideal tool for translation to clinical investigations. MRI, while still behind in molecular imaging strategies compared to PET and SPECT, has the great advantage to have a high spatial resolution and no need for the injection of a contrast-agent or radio-labeled molecules, thereby avoiding the repetitive exposure to ionizing radiations. Functional MRI (fMRI) is extensively used in research and clinical setting, where it is generally combined with a psycho-motor task. phMRI is an adaptation of fMRI enabling the investigation of a specific neurotransmitter system, such as serotonin (5-HT), under physiological or pathological conditions following activation via administration of a specific challenging drug. The aim of the method described here is to assess brain 5-HT function in free-breathing animals. By challenging the 5-HT system while simultaneously acquiring functional MR images over time, the response of the brain to this challenge can be visualized. Several studies in animals have already demonstrated that drug-induced increases in extracellular levels of e.g. 5-HT (releasing agents, selective re-uptake blockers, etc) evoke region-specific changes in blood oxygenation level dependent (BOLD) MRI signals (signal due to a change of the oxygenated/deoxygenated hemoglobin levels occurring during brain activation through an increase of the blood supply to supply the oxygen and glucose to the demanding neurons) providing an index of neurotransmitter function. It has also been shown that these effects can be reversed by treatments that decrease 5-HT availability16,13,18,7. In adult rats, BOLD signal changes following acute SSRI administration have been described in several 5-HT related brain regions, i.e. cortical areas, hippocampus, hypothalamus and thalamus9,16,15. Stimulation of the 5-HT system and its response to this challenge can be thus used as a measure of its function in both animals and humans2,11.
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Affiliation(s)
- Anne Klomp
- Department of Radiology, Brain Imaging Center, Academic Medical Center Amsterdam
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