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Sanches ES, Boia R, Leitão RA, Madeira MH, Fontes-Ribeiro CA, Ambrósio AF, Fernandes R, Silva AP. Attention-Deficit/Hyperactivity Disorder Animal Model Presents Retinal Alterations and Methylphenidate Has a Differential Effect in ADHD versus Control Conditions. Antioxidants (Basel) 2023; 12:antiox12040937. [PMID: 37107312 PMCID: PMC10135983 DOI: 10.3390/antiox12040937] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/07/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
Attention-Deficit/Hyperactivity Disorder (ADHD) is one of the most prevalent neurodevelopmental disorders. Interestingly, children with ADHD seem to experience more ophthalmologic abnormalities, and the impact of methylphenidate (MPH) use on retinal physiology remains unclear. Thus, we aimed to unravel the retina's structural, functional, and cellular alterations and the impact of MPH in ADHD versus the control conditions. For that, spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY) were used as animal models of ADHD and the controls, respectively. Animals were divided into four experimental groups as follows: WKY vehicle (Veh; tap water), WKY MPH (1.5 mg/kg/day), SHR Veh, SHR MPH. Individual administration was performed by gavage between P28-P55. Retinal physiology and structure were evaluated at P56 followed by tissue collection and analysis. The ADHD animal model presents the retinal structural, functional, and neuronal deficits, as well as the microglial reactivity, astrogliosis, blood-retinal barrier (BRB) hyperpermeability and a pro-inflammatory status. In this model, MPH had a beneficial effect on reducing microgliosis, BRB dysfunction, and inflammatory response, but did not correct the neuronal and functional alterations in the retina. Curiously, in the control animals, MPH showed an opposite effect since it impaired the retinal function, neuronal cells, and BRB integrity, and also promoted both microglia reactivity and upregulation of pro-inflammatory mediators. This study unveils the retinal alterations in ADHD and the opposite effects induced by MPH in the retina of ADHD and the control animal models.
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Affiliation(s)
- Eliane S Sanches
- Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-531 Coimbra, Portugal
| | - Raquel Boia
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-531 Coimbra, Portugal
- Clinical Academic Center of Coimbra (CACC), 3004-561 Coimbra, Portugal
| | - Ricardo A Leitão
- Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-531 Coimbra, Portugal
| | - Maria H Madeira
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-531 Coimbra, Portugal
| | - Carlos A Fontes-Ribeiro
- Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-531 Coimbra, Portugal
- Clinical Academic Center of Coimbra (CACC), 3004-561 Coimbra, Portugal
| | - António Francisco Ambrósio
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-531 Coimbra, Portugal
- Clinical Academic Center of Coimbra (CACC), 3004-561 Coimbra, Portugal
- Association for Innovation and Biomedical Research on Light and Image (AIBILI), 3000-548 Coimbra, Portugal
| | - Rosa Fernandes
- Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-531 Coimbra, Portugal
- Clinical Academic Center of Coimbra (CACC), 3004-561 Coimbra, Portugal
- Association for Innovation and Biomedical Research on Light and Image (AIBILI), 3000-548 Coimbra, Portugal
| | - Ana Paula Silva
- Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-531 Coimbra, Portugal
- Clinical Academic Center of Coimbra (CACC), 3004-561 Coimbra, Portugal
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Liu X, Huang H, Snutch TP, Cao P, Wang L, Wang F. The Superior Colliculus: Cell Types, Connectivity, and Behavior. Neurosci Bull 2022; 38:1519-1540. [PMID: 35484472 DOI: 10.1007/s12264-022-00858-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 02/16/2022] [Indexed: 10/18/2022] Open
Abstract
The superior colliculus (SC), one of the most well-characterized midbrain sensorimotor structures where visual, auditory, and somatosensory information are integrated to initiate motor commands, is highly conserved across vertebrate evolution. Moreover, cell-type-specific SC neurons integrate afferent signals within local networks to generate defined output related to innate and cognitive behaviors. This review focuses on the recent progress in understanding of phenotypic diversity amongst SC neurons and their intrinsic circuits and long-projection targets. We further describe relevant neural circuits and specific cell types in relation to behavioral outputs and cognitive functions. The systematic delineation of SC organization, cell types, and neural connections is further put into context across species as these depend upon laminar architecture. Moreover, we focus on SC neural circuitry involving saccadic eye movement, and cognitive and innate behaviors. Overall, the review provides insight into SC functioning and represents a basis for further understanding of the pathology associated with SC dysfunction.
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Affiliation(s)
- Xue Liu
- Shenzhen Key Lab of Neuropsychiatric Modulation, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hongren Huang
- Shenzhen Key Lab of Neuropsychiatric Modulation, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Terrance P Snutch
- Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | - Peng Cao
- National Institute of Biological Sciences, Beijing, 100049, China
| | - Liping Wang
- Shenzhen Key Lab of Neuropsychiatric Modulation, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China.
| | - Feng Wang
- Shenzhen Key Lab of Neuropsychiatric Modulation, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Key Laboratory of Brain Connectome and Manipulation, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China.
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Droguerre M, Vidal B, Valdebenito M, Mouthon F, Zimmer L, Charvériat M. Impaired Local and Long-Range Brain Connectivity and Visual Response in a Genetic Rat Model of Hyperactivity Revealed by Functional Ultrasound. Front Neurosci 2022; 16:865140. [PMID: 35401075 PMCID: PMC8987929 DOI: 10.3389/fnins.2022.865140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 02/21/2022] [Indexed: 11/13/2022] Open
Abstract
Attention-Deficit hyperactivity disorder (ADHD) is a central nervous system (CNS) disorder frequently associated with other psychiatric disorders. Pathophysiology processes at stake in ADHD are still under investigation and interestingly neuroimaging data points to modulated brain connectivity in patients. The genetic spontaneously hypertensive rat (SHR) model has been widely used to study pathophysiological underpinnings of ADHD and resting-state brain connectivity using functional magnetic resonance imaging. Here, functional ultrasound imaging, a new technique enabling fast measurement of cerebral blood volume (CBV), was used to further characterize resting-state functional connectivity – at both local and long-range – and visual response in SHR. We demonstrated that response to visual stimulation was increased in SHR in the visual cortex and the superior colliculus. They displayed altered long-range functional connectivity between spatially distinct regions. SHR also displayed modulated local connectivity, with strong increases of regional homogeneity in parts of the motor and visual cortex, along with decreases in the secondary cingulate cortex, the superior colliculus and the pretectal area. As CBV is intricately coupled to cerebral activity, these results suggest an abnormal neural activity in the SHR animal model, consistent with previous clinical studies and demonstrate the potential of functional ultrasound imaging as a translational tool in ADHD.
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Affiliation(s)
| | - Benjamin Vidal
- Theranexus, Lyon, France
- CNRS, UMR 5292, INSERM U1028, Lyon Neuroscience Research Center, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France
- *Correspondence: Benjamin Vidal,
| | | | | | - Luc Zimmer
- CNRS, UMR 5292, INSERM U1028, Lyon Neuroscience Research Center, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France
- CERMEP-Imaging Platform, Bron, France
- Hospices Civils de Lyon, Lyon, France
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Amphetamine-induced alteration to gaze parameters: A novel conceptual pathway and implications for naturalistic behavior. Prog Neurobiol 2020; 199:101929. [PMID: 33091542 DOI: 10.1016/j.pneurobio.2020.101929] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 09/03/2020] [Accepted: 10/08/2020] [Indexed: 12/25/2022]
Abstract
Amphetamine produces a multiplicity of well-documented end-order biochemical, pharmacological and biobehavioural effects. Mechanistically, amphetamine downregulates presynaptic and postsynaptic striatal monoamine (primarily dopaminergic) systems, producing alterations to key brain regions which manifest as stereotyped ridged behaviour which occurs under both acute and chronic dosing schedules and persists beyond detoxification. Despite evidence of amphetamine-induced visual attentional dysfunction, no conceptual synthesis has yet captured how characteristic pharmaco-behavioural processes are critically implicated via these pathways, nor described the potential implications for safety-sensitive behaviours. Drawing on known pathomechanisms, we propose a cross-disciplinary, novel conceptual functional system framework for delineating the biobehavioural consequences of amphetamine use on visual attentional capacity and discuss the implications for functional and behavioural outcomes. Specifically, we highlight the manifest implications for behaviours that are conceptually driven and highly dependent on visual information processing for timely execution of visually-guided movements. Following this, we highlight the potential impact on safety-sensitive, but common behaviours, such as driving a motor vehicle. The close pathophysiological relationship between oculomotor control and higher-order cognitive processes further suggests that dynamic measurement of movement related to the motion of the eye (gaze behaviour) may be a simple, effective and direct measure of behavioural performance capabilities in naturalistic settings. Consequently, we discuss the potential efficacy of ocular monitoring for the detection and monitoring of driver states for this drug user group, and potential wider application. Significance statement: We propose a novel biochemical-physiological-behavioural pathway which delineates how amphetamine use critically alters oculomotor function, visual-attentional performance and information processing capabilities. Given the manifest implications for behaviours that are conceptually driven and highly dependent on these processes, we recommend oculography as a novel means of detecting and monitoring gaze behaviours during naturalistic tasks such as driving. Real-word examination of gaze behaviour therefore present as an effective means to detect driver impairment and prevent performance degradation due to these drugs.
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Sánchez-Guillén I, Almorín-Fernández-Vigo I, Fernández-Vigo JI, de-Pablo-Gómez-de-Liaño L, Kudsieh B, Fernández-Vigo JA. Assessment of changes in the macula and optic nerve head using optical coherence tomography in patients with attention deficit hyperactivity disorder. ACTA ACUST UNITED AC 2020; 95:271-278. [PMID: 32423628 DOI: 10.1016/j.oftal.2020.02.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Revised: 02/25/2020] [Accepted: 02/27/2020] [Indexed: 12/21/2022]
Abstract
INTRODUCTION To assess if there are any differences in macular and papillary thickness using optical coherence tomography (OCT) in patients with attention deficit hyperactivity disorder (ADHD) compared with a control group, including if there are differences between ADHD patients with and without treatment. METHODS Prospective observational study including 92 eyes of 46 patients divided into 2 groups: 46 eyes of 23 patients with ADHD, and a control group of 46 eyes of 23 healthy patients. The group of patients with ADHD was subdivided into those on treatment with methylphenidate (n=28) and those not on treatment (n=18). The macular thickness, the ganglion cell complex (GCC), and the retinal nerve fibre layer (RNFL) at the papillary level were measured in 12 sectors. RESULTS A lower central macular thickness was observed in the ADHD patients than in the controls (257.4±20μm versus 267.5±20μm, P=.013), with no differences observed in the GCC (P=.566), or in the RNFL (P=.095). There were no differences in the patients with ADHD with and without treatment, as regards macular thickness and the GCC (P=.160 and P=.375 respectively), but a lower foveal thickness (P=.018) and RNFL in 5/12 sectors at the papillary level (P=.033) were observed in those without treatment. CONCLUSIONS A lower macular thickness was observed in patients with ADHD than in controls. In addition, patients with ADHD without treatment had a lower thickness of the fovea and RNFL than those patients on treatment.
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Affiliation(s)
- I Sánchez-Guillén
- Centro Internacional de Oftalmología Avanzada, Badajoz, España; Departamento de Oftalmología, Hospital de Zafra, Zafra, Badajoz, España.
| | | | - J I Fernández-Vigo
- Centro Internacional de Oftalmología Avanzada, Madrid, España; Departamento de Oftalmología, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, España
| | - L de-Pablo-Gómez-de-Liaño
- Centro Internacional de Oftalmología Avanzada, Madrid, España; Departamento de Oftalmología, Hospital 12 de Octubre, Madrid, España
| | - B Kudsieh
- Centro Internacional de Oftalmología Avanzada, Madrid, España; Departamento de Oftalmología, Hospital Puerta de Hierro, Majadahonda, Madrid, España
| | - J A Fernández-Vigo
- Centro Internacional de Oftalmología Avanzada, Badajoz, España; Centro Internacional de Oftalmología Avanzada, Madrid, España; Facultad de Medicina, Universidad de Extremadura, Badajoz, España
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The influence of subcortical shortcuts on disordered sensory and cognitive processing. Nat Rev Neurosci 2020; 21:264-276. [PMID: 32269315 DOI: 10.1038/s41583-020-0287-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/28/2020] [Indexed: 12/14/2022]
Abstract
The very earliest stages of sensory processing have the potential to alter how we perceive and respond to our environment. These initial processing circuits can incorporate subcortical regions, such as the thalamus and brainstem nuclei, which mediate complex interactions with the brain's cortical processing hierarchy. These subcortical pathways, many of which we share with other animals, are not merely vestigial but appear to function as 'shortcuts' that ensure processing efficiency and preservation of vital life-preserving functions, such as harm avoidance, adaptive social interactions and efficient decision-making. Here, we propose that functional interactions between these higher-order and lower-order brain areas contribute to atypical sensory and cognitive processing that characterizes numerous neuropsychiatric disorders.
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Gass N, Becker R, Reinwald J, Cosa-Linan A, Sack M, Weber-Fahr W, Vollmayr B, Sartorius A. The influence of ketamine's repeated treatment on brain topology does not suggest an antidepressant efficacy. Transl Psychiatry 2020; 10:56. [PMID: 32066682 PMCID: PMC7026038 DOI: 10.1038/s41398-020-0727-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 11/04/2019] [Accepted: 11/04/2019] [Indexed: 02/06/2023] Open
Abstract
As ketamine is increasingly used as an effective antidepressant with rapid action, sustaining its short-lived efficacy over a longer period of time using a schedule of repeated injections appears as an option. An open question is whether repeated and single administrations would affect convergent neurocircuits. We used a combination of one of the most robust animal models of depression with high-field neuroimaging to perform a whole-brain delineation of functional mechanisms underlying ketamine's effects. Rats from two genetic strains, depressive-like and resilient, received seven treatments of 10 mg/kg S-ketamine (N = 14 depressive-like, N = 11 resilient) or placebo (N = 12 depressive-like, N = 10 resilient) and underwent resting-state functional magnetic resonance imaging. Using graph theoretical models of brain networks, we compared effects of repeated ketamine with those of single administration from a separate dataset of our previous study. Compared to single treatment, repeated ketamine evoked strain-specific brain network randomization, resembling characteristics of the depressive-like strain and patients. Several affected regions belonged to the auditory, visual, and motor circuitry, hinting at possible cumulative side effects. Finally, when compared to saline, repeated ketamine affected only a few local topological properties and had no effects on global properties. In combination with the lack of clear differences compared to placebo, our findings point toward an inefficacy of ketamine's long-term administration on brain topology, making questionable the postulated effect of repeated administration and being consistent with the recently reported absence of repeated ketamine's antidepressant efficacy in several placebo-controlled studies.
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Affiliation(s)
- Natalia Gass
- Research Group Translational Imaging, Department of Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
| | - Robert Becker
- grid.7700.00000 0001 2190 4373Research Group Translational Imaging, Department of Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Jonathan Reinwald
- grid.7700.00000 0001 2190 4373Research Group Translational Imaging, Department of Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany ,grid.7700.00000 0001 2190 4373Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Alejandro Cosa-Linan
- grid.7700.00000 0001 2190 4373Research Group In Silico Pharmacology, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Markus Sack
- grid.7700.00000 0001 2190 4373Research Group Translational Imaging, Department of Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Wolfgang Weber-Fahr
- grid.7700.00000 0001 2190 4373Research Group Translational Imaging, Department of Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Barbara Vollmayr
- grid.7700.00000 0001 2190 4373Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany ,grid.7700.00000 0001 2190 4373Research Group Animal Models in Psychiatry, Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Alexander Sartorius
- grid.7700.00000 0001 2190 4373Research Group Translational Imaging, Department of Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany ,grid.7700.00000 0001 2190 4373Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
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Jansen K, Hanusch B, Pross S, Hanff E, Drabert K, Bollenbach A, Dugave I, Carmann C, Siefen RG, Emons B, Juckel G, Legenbauer T, Tsikas D, Lücke T. Enhanced Nitric Oxide (NO) and Decreased ADMA Synthesis in Pediatric ADHD and Selective Potentiation of NO Synthesis by Methylphenidate. J Clin Med 2020; 9:jcm9010175. [PMID: 31936392 PMCID: PMC7019361 DOI: 10.3390/jcm9010175] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 12/27/2019] [Accepted: 01/04/2020] [Indexed: 12/12/2022] Open
Abstract
Attention deficit hyperactivity disorder (ADHD) is a common pediatric psychiatric disorder, frequently treated with methylphenidate (MPH). Recently, MPH’s cardiovascular safety has been questioned by observational studies describing an increased cardiovascular risk in adults and blood pressure alterations in children. We considered members of the L-arginine (Arg)/nitric oxide (NO) pathway as possible early cardiovascular risk factors in pediatric ADHD children. They include the NO metabolites, nitrite and nitrate, the NO precursor Arg, and asymmetric dimethylarginine (ADMA), an endogenous NO synthase (NOS) inhibitor and a cardiovascular risk factor in adults. We conducted a prospective clinical trial with 42 ADHD children (aged 6–16 years) with (n = 19) and without (n = 23) MPH treatment. Age-matched children without ADHD (n = 43) served as controls. All plasma and urine metabolites were determined by gas chromatography-mass spectrometry. We observed higher plasma nitrite and lower plasma ADMA concentrations in the ADHD children. MPH-treated ADHD children had higher plasma nitrite concentrations than MPH-untreated ADHD children. As NOS activity is basally inhibited by ADMA, MPH treatment seems to have decreased the inhibitory potency of ADMA. Percentiles of systolic blood pressure were higher in MPH-treated ADHD children. The underlying mechanisms and their implications in the MPH therapy of pediatric ADHD with MPH remain to be elucidated in larger cohorts.
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Affiliation(s)
- Kathrin Jansen
- University Children’s Hospital, Ruhr University Bochum, 44791 Bochum, Germany
- Correspondence: ; Tel.: +49-234-5092615
| | - Beatrice Hanusch
- University Children’s Hospital, Ruhr University Bochum, 44791 Bochum, Germany
| | - Saskia Pross
- University Children’s Hospital, Ruhr University Bochum, 44791 Bochum, Germany
- Children’s Hospital, St., Clemens-Hospital Geldern, 47608 Geldern, Germany
| | - Erik Hanff
- Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, 30625 Hannover, Germany
| | - Kathrin Drabert
- Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, 30625 Hannover, Germany
| | - Alexander Bollenbach
- Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, 30625 Hannover, Germany
| | - Irina Dugave
- University Children’s Hospital, Ruhr University Bochum, 44791 Bochum, Germany
- Department of Psychiatry, Alexius/Josef Hospital, 41464 Neuss, Germany
| | - Christina Carmann
- University Children’s Hospital, Ruhr University Bochum, 44791 Bochum, Germany
| | - Rainer Georg Siefen
- University Children’s Hospital, Ruhr University Bochum, 44791 Bochum, Germany
| | - Barbara Emons
- Department of Psychiatry, LWL Institute of Mental Health, LWL University Hospital, Ruhr-University Bochum, 44791 Bochum, Germany
- Department of Psychiatry, LWL University Hospital, Ruhr-University Bochum, 44791 Bochum, Germany
| | - Georg Juckel
- Department of Psychiatry, LWL Institute of Mental Health, LWL University Hospital, Ruhr-University Bochum, 44791 Bochum, Germany
- Department of Psychiatry, LWL University Hospital, Ruhr-University Bochum, 44791 Bochum, Germany
| | - Tanja Legenbauer
- LWL University Hospital Hamm for Child and Adolescent Psychiatry, Psychotherapy and Psychosomatic, Ruhr University Bochum, 59071 Hamm, Germany
| | - Dimitrios Tsikas
- Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, 30625 Hannover, Germany
| | - Thomas Lücke
- University Children’s Hospital, Ruhr University Bochum, 44791 Bochum, Germany
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Riley TB, Overton PG. Enhancing the efficacy of 5-HT uptake inhibitors in the treatment of attention deficit hyperactivity disorder. Med Hypotheses 2019; 133:109407. [PMID: 31586811 DOI: 10.1016/j.mehy.2019.109407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 09/19/2019] [Accepted: 09/24/2019] [Indexed: 10/26/2022]
Abstract
Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common childhood behavioural disorders, the frontline treatments for which are drugs with abuse potential. As a consequence, there is an urgent need to develop non addictive drug treatments with equivalent efficacy. Preclinical evidence suggests that selective serotonin uptake inhibitors (SSRIs) are likely to be effective in ADHD, however clinical reports suggest that SSRIs are of limited therapeutic value for the treatment of ADHD. We propose that this disconnect can be explained by the pattern of drug administration in existing clinical trials (administration for short periods of time, or intermittently) leading to inadequate control of the autoregulatory processes which control 5-HT release, most notably at the level of inhibitory 5-HT1A somatodendritic autoreceptors. These autoreceptors reduce the firing rate of 5-HT neurons (limiting release) unless they are desensitised by a long term, frequent pattern of drug administration. As such, we argue that the participants in earlier trials were not administered SSRIs in a manner which realises any potential benefits of targeting 5-HT in the pharmacotherapy of ADHD. In light of this, we hypothesise that there may be under-researched potential to exploit 5-HT transmission therapeutically in ADHD, either through changing the administration regime, or by pharmacological means. Recent pharmacological research has successfully potentiated the effects of SSRIs in acute animal preparations by antagonising inhibitory 5-HT1A autoreceptors prior to the administration of the SSRI fluoxetine. We suggest that combination therapies linking SSRIs and 5-HT1A antagonists are a potential way forward in the development of efficacious non-addictive pharmacotherapies for ADHD.
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Affiliation(s)
- Timothy B Riley
- Department of Psychology, University of Sheffield, Sheffield S10 2TP, UK
| | - Paul G Overton
- Department of Psychology, University of Sheffield, Sheffield S10 2TP, UK
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Mihali A, Young AG, Adler LA, Halassa MM, Ma WJ. A Low-Level Perceptual Correlate of Behavioral and Clinical Deficits in ADHD. COMPUTATIONAL PSYCHIATRY (CAMBRIDGE, MASS.) 2018; 2:141-163. [PMID: 30381800 PMCID: PMC6184361 DOI: 10.1162/cpsy_a_00018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 07/10/2018] [Indexed: 11/04/2022]
Abstract
In many studies of attention-deficit hyperactivity disorder (ADHD), stimulus encoding and processing (perceptual function) and response selection (executive function) have been intertwined. To dissociate deficits in these functions, we introduced a task that parametrically varied low-level stimulus features (orientation and color) for fine-grained analysis of perceptual function. It also required participants to switch their attention between feature dimensions on a trial-by-trial basis, thus taxing executive processes. Furthermore, we used a response paradigm that captured task-irrelevant motor output (TIMO), reflecting failures to use the correct stimulus-response rule. ADHD participants had substantially higher perceptual variability than controls, especially for orientation, as well as higher TIMO. In both ADHD and controls, TIMO was strongly affected by the switch manipulation. Across participants, the perceptual variability parameter was correlated with TIMO, suggesting that perceptual deficits are associated with executive function deficits. Based on perceptual variability alone, we were able to classify participants into ADHD and controls with a mean accuracy of about 77%. Participants' self-reported General Executive Composite score correlated not only with TIMO but also with the perceptual variability parameter. Our results highlight the role of perceptual deficits in ADHD and the usefulness of computational modeling of behavior in dissociating perceptual from executive processes.
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Affiliation(s)
- Andra Mihali
- Center for Neural Science, New York University, New York, New York, USA
- Department of Psychology, New York University, New York, New York, USA
| | - Allison G. Young
- Department of Psychiatry, NYU School of Medicine, New York, New York, USA
| | - Lenard A. Adler
- Department of Psychiatry, NYU School of Medicine, New York, New York, USA
| | - Michael M. Halassa
- Department of Brain and Cognitive Science, MIT, Boston, Massachusetts, USA
| | - Wei Ji Ma
- Center for Neural Science, New York University, New York, New York, USA
- Department of Psychology, New York University, New York, New York, USA
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11
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Chronic amphetamine enhances visual input to and suppresses visual output from the superior colliculus in withdrawal. Neuropharmacology 2018; 138:118-129. [DOI: 10.1016/j.neuropharm.2018.05.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 05/01/2018] [Accepted: 05/30/2018] [Indexed: 11/23/2022]
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12
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Turner AC, Stramek A, Kraev I, Stewart MG, Overton PG, Dommett EJ. Chronic amphetamine treatment affects collicular-dependent behaviour. Behav Brain Res 2018; 343:1-7. [PMID: 29407411 DOI: 10.1016/j.bbr.2018.01.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 01/10/2018] [Accepted: 01/22/2018] [Indexed: 12/26/2022]
Abstract
Distractibility can be defined as an attention deficit where orientation toward irrelevant targets cannot be inhibited. There is now mounting evidence that the superior colliculus is a key neural correlate of distractibility, with increased collicular-activity resulting in heightened distractibility. Heightened distractibility is reduced by amphetamine, which acutely suppresses collicular responsiveness. However, when amphetamine is used to treat distractibility, it is given chronically, yet no data exist on whether chronic amphetamine treatment affects the colliculus. Here, the effect of chronic amphetamine treatment was assessed in healthy hooded lister rats on two collicular dependent behaviours following a twenty-eight day treatment period: i) orienting to visual stimuli, and ii) height-dependent modulation of air-righting. We found no significant impact of amphetamine treatment on visual orienting despite showing dose-dependent decreases in orienting to repeated stimuli. However, we did find that treatment with amphetamine significantly reduced the ability to modulate righting according to the height the animal is dropped from - a function known to be dependent on the colliculus. We suggest that the results are in line with previous research showing acute amphetamine suppresses collicular activity and we speculate that the psychostimulant may increase receptive field size, altering time-to-impact calculations carried out by the colliculus during air-righting.
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Affiliation(s)
- Amy C Turner
- School of Life, Health and Chemical Sciences, The Open University, Milton Keynes, MK7 6AA, UK
| | - Agata Stramek
- School of Life, Health and Chemical Sciences, The Open University, Milton Keynes, MK7 6AA, UK
| | - Igor Kraev
- School of Life, Health and Chemical Sciences, The Open University, Milton Keynes, MK7 6AA, UK
| | - Michael G Stewart
- School of Life, Health and Chemical Sciences, The Open University, Milton Keynes, MK7 6AA, UK
| | - Paul G Overton
- Department of Psychology, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Eleanor J Dommett
- School of Life, Health and Chemical Sciences, The Open University, Milton Keynes, MK7 6AA, UK; Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, SE5 8AF, UK.
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13
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Alexander RG, Macknik SL, Martinez-Conde S. Microsaccade Characteristics in Neurological and Ophthalmic Disease. Front Neurol 2018; 9:144. [PMID: 29593642 PMCID: PMC5859063 DOI: 10.3389/fneur.2018.00144] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 02/27/2018] [Indexed: 12/01/2022] Open
Abstract
Microsaccade research has recently reached a critical mass of studies that allows, for the first time, a comprehensive review of how microsaccadic dynamics change in neurological and ophthalmic disease. We discuss the various pathological conditions that affect microsaccades, their impact on microsaccadic and other fixational eye movement dynamics, and the incipient studies that point to microsaccadic features as potential indicators of differential and early diagnoses of multiple clinical conditions, from movement disorders to attention-deficit hyperactivity disorder to amblyopia. We propose that the objective assessment of fixational eye movement parameters may help refine differential diagnostics in neurological disease and assist in the evaluation of ongoing therapy regimes. In addition, determining the effects of ophthalmic disease on fixational eye movement features may help evaluate visual impairment in an objective manner, particularly in young patients or those experiencing communication difficulties.
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Affiliation(s)
- Robert G Alexander
- State University of New York (SUNY) Downstate Medical Center, Brooklyn, NY, United States
| | - Stephen L Macknik
- State University of New York (SUNY) Downstate Medical Center, Brooklyn, NY, United States
| | - Susana Martinez-Conde
- State University of New York (SUNY) Downstate Medical Center, Brooklyn, NY, United States
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14
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Hetherington L, Dommett EJ, Turner AC, Riley TB, Haensel JX, Overton PG. Effect of methylphenidate on visual responses in the superior colliculus in the anaesthetised rat: Role of cortical activation. J Psychopharmacol 2017; 31:1347-1361. [PMID: 28925314 DOI: 10.1177/0269881117730661] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The mechanism of action of psychostimulant drugs in the treatment of Attention Deficit Hyperactivity Disorder is still largely unknown, although recent evidence suggests one possibility is that the drugs affect the superior colliculus (SC). We have previously demonstrated that systemically administered d-amphetamine attenuates/abolishes visual responses to wholefield light flashes in the superficial layers of the SC in anaesthetised rats, and the present study sought to extend this work to methylphenidate (MPH). Anaesthetised rats were administered MPH at a range of doses (or saline) and subjected to monocular wholefield light flashes at two intensities, juxta-threshold and super-threshold. In contrast to d-amphetamine, systemic MPH produced an enhancement of visual activity at both intensities. Methylphenidate was also found to produce activation of the cortical EEG in anaesthetised rats. Furthermore, cortical activation induced by electrical stimulation of the pons was found to enhance visual responses in superficial layers of the SC, and when MPH was paired with pontine-induced cortical activation, the response-enhancing effects of MPH were substantially attenuated. Taken together, the results suggest that the enhancement of visual responses in the superficial layers of the SC by MPH in the anaesthetised rat is an artefact of the drug's interaction with cortical arousal.
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Affiliation(s)
- L Hetherington
- 1 Department of Psychology, University of Sheffield, Sheffield, UK
| | - E J Dommett
- 2 Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - A C Turner
- 3 School of Life, Health and Chemical Sciences, The Open University, Milton Keynes, UK
| | - T B Riley
- 1 Department of Psychology, University of Sheffield, Sheffield, UK
| | - J X Haensel
- 4 Department of Psychological Sciences, Birkbeck, University of London, London, UK
| | - P G Overton
- 1 Department of Psychology, University of Sheffield, Sheffield, UK
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15
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Panagiotidi M, Overton PG, Stafford T. Attention-Deficit Hyperactivity Disorder-Like Traits and Distractibility in the Visual Periphery. Perception 2016; 46:665-678. [DOI: 10.1177/0301006616681313] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
We examined the performance of nonclinical subjects with high and low levels of self-reported attention-deficit hyperactivity disorder (ADHD)-like traits in a novel distractibility paradigm with far peripheral visual distractors, the likely origin of many distractors in everyday life. Subjects were tested on a Sustained Attention to Response Task with distractors appearing before some of the target or nontarget stimuli. When the distractors appeared 80 ms before the targets or nontargets, participants with high levels of ADHD-like traits were less affected in their reaction times than those with lower levels. Reducing the distractor-target or nontarget interval to 10 ms removed the reaction time advantage for the high group. We suggest that at 80 ms, the distractors were cueing the arrival of the target or nontarget, and that those with high levels of ADHD-like traits were more sensitive to the cues. Increased sensitivity to stimuli in the visual periphery is consistent with hyperresponsiveness at the level of the superior colliculus.
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Affiliation(s)
| | - Paul G. Overton
- Department of Psychology, University of Sheffield, Western Bank, UK
| | - Tom Stafford
- Department of Psychology, University of Sheffield, Western Bank, UK
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16
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Brace LR, Kraev I, Rostron CL, Stewart MG, Overton PG, Dommett EJ. Auditory responses in a rodent model of Attention Deficit Hyperactivity Disorder. Brain Res 2015; 1629:10-25. [PMID: 26453290 DOI: 10.1016/j.brainres.2015.09.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 09/28/2015] [Accepted: 09/29/2015] [Indexed: 01/30/2023]
Abstract
A central component of Attention Deficit Hyperactivity Disorder (ADHD) is increased distractibility in response to visual and auditory stimuli, which is linked to the superior colliculus (SC). Furthermore, there is now mounting evidence of altered collicular functioning in ADHD and it is proposed that a hyper-responsive SC could mediate symptoms of ADHD, including distractibility. In the present study we conducted a systematic characterisation of the intermediate and deep layers of the SC in the most commonly used and well-validated model of ADHD, the spontaneously hypertensive rat (SHR), building on prior work showing increased distractible behaviour in this strain using visual distractors. We examined collicular-dependent orienting behaviour, local field potential (LFP) and multiunit activity (MUA) in response to auditory stimuli in the anaesthetised rat, and morphological measures, in the SHR in comparison to the Wistar Kyoto (WKY) and Wistar (WIS). We found no evidence of increased distractibility in the behavioural data but suggest that this may arise due to cochlear hearing loss in the SHR. Furthermore, the electrophysiology data indicate that the SC in the SHR may still be hyper-responsive, normalising the amplitude of auditory responses that would otherwise be reduced due to the hearing impairment. The morphological measures of collicular volume, cell density and ratios did not indicate this potential hyper-responsiveness had a basis at the structural level examined. These findings have implications for future use of the SHR in auditory processing studies and may represent a limitation to the validity of this animal model.
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Affiliation(s)
- Louise R Brace
- Department of Life, Health and Chemical Sciences, The Open University, Milton Keynes MK7 6AA, UK
| | - Igor Kraev
- Department of Life, Health and Chemical Sciences, The Open University, Milton Keynes MK7 6AA, UK
| | - Claire L Rostron
- Department of Life, Health and Chemical Sciences, The Open University, Milton Keynes MK7 6AA, UK
| | - Michael G Stewart
- Department of Life, Health and Chemical Sciences, The Open University, Milton Keynes MK7 6AA, UK
| | - Paul G Overton
- Department of Psychology, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - Eleanor J Dommett
- Department of Life, Health and Chemical Sciences, The Open University, Milton Keynes MK7 6AA, UK; Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King׳s College London, London SE1 3QD, UK.
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17
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Altered visual processing in a rodent model of Attention-Deficit Hyperactivity Disorder. Neuroscience 2015; 303:364-77. [DOI: 10.1016/j.neuroscience.2015.07.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 06/18/2015] [Accepted: 07/01/2015] [Indexed: 11/23/2022]
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18
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Riley E, Kopotiyenko K, Zhdanova I. Prenatal and acute cocaine exposure affects neural responses and habituation to visual stimuli. Front Neural Circuits 2015; 9:41. [PMID: 26379509 PMCID: PMC4548223 DOI: 10.3389/fncir.2015.00041] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 08/04/2015] [Indexed: 12/17/2022] Open
Abstract
Psychostimulants have many effects on visual function, from adverse following acute and prenatal exposure to therapeutic on attention deficit. To determine the impact of prenatal and acute cocaine exposure on visual processing, we studied neuronal responses to visual stimuli in two brain regions of a transgenic larval zebrafish expressing the calcium indicator GCaMP-HS. We found that both red light (LF) and dark (DF) flashes elicited similar responses in the optic tectum neuropil (TOn), while the dorsal telencephalon (dTe) responded only to LF. Acute cocaine (0.5 μM) reduced neuronal responses to LF in both brain regions but did not affect responses to DF. Repeated stimulus presentation (RSP) led to habituation of dTe neurons to LF. Acute cocaine prevented habituation. TOn habituated to DF, but not LF, and DF habituation was not modified by cocaine. Remarkably, prenatal cocaine exposure (PCE) prevented the effects of acute cocaine on LF response amplitude and habituation later in development in both brain regions, but did not affect DF responses. We discovered that, in spite of similar neural responses to LF and DF in the TO (superior colliculus in mammals), responses to LF are more complex, involving dTe (homologous to the cerebral cortex), and are more vulnerable to cocaine. Our results demonstrate that acute cocaine exposure affects visual processing differentially by brain region, and that PCE modifies zebrafish visual processing in multiple structures in a stimulus-dependent manner. These findings are in accordance with the major role that the optic tectum and cerebral cortex play in sustaining visual attention, and support the hypothesis that modification of these areas by PCE may be responsible for visual deficits noted in humans. This model offers new methodological approaches for studying the adverse and therapeutic effects of psychostimulants on attention, and for the development of new pharmacological interventions.
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Affiliation(s)
- Elizabeth Riley
- Boston University Graduate Program in Neuroscience, Boston University School of Medicine Boston, MA, USA
| | - Konstantin Kopotiyenko
- Department of Anatomy and Neurobiology, Boston University School of Medicine Boston, MA, USA
| | - Irina Zhdanova
- Boston University Graduate Program in Neuroscience, Boston University School of Medicine Boston, MA, USA ; Department of Anatomy and Neurobiology, Boston University School of Medicine Boston, MA, USA
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19
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Bayguinov PO, Ghitani N, Jackson MB, Basso MA. A hard-wired priority map in the superior colliculus shaped by asymmetric inhibitory circuitry. J Neurophysiol 2015; 114:662-76. [PMID: 25995346 PMCID: PMC4512250 DOI: 10.1152/jn.00144.2015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 05/20/2015] [Indexed: 11/22/2022] Open
Abstract
The mammalian superior colliculus (SC) is a laminar midbrain structure that translates visual signals into commands to shift the focus of attention and gaze. The SC plays an integral role in selecting targets and ultimately generating rapid eye movements to those targets. In all mammals studied to date, neurons in the SC are arranged topographically such that the location of visual stimuli and the endpoints of orienting movements form organized maps in superficial and deeper layers, respectively. The organization of these maps is thought to underlie attentional priority by assessing which regions of the visual field contain behaviorally relevant information. Using voltage imaging and patch-clamp recordings in parasagittal SC slices from the rat, we found the synaptic circuitry of the visuosensory map in the SC imposes a strong bias. Voltage imaging of responses to electrical stimulation revealed more spread in the caudal direction than the rostral direction. Pharmacological experiments demonstrated that this asymmetry arises from GABAA receptor activation rostral to the site of stimulation. Patch-clamp recordings confirmed this rostrally directed inhibitory circuit and showed that it is contained within the visuosensory layers of the SC. Stimulation of two sites showed that initial stimulation of a caudal site can take priority over subsequent stimulation of a rostral site. Taken together, our data indicate that the circuitry of the visuosensory SC is hard-wired to give higher priority to more peripheral targets, and this property is conferred by a uniquely structured, dedicated inhibitory circuit.
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Affiliation(s)
- Peter O Bayguinov
- Department of Neuroscience, University of Wisconsin, Madison, Wisconsin
| | - Nima Ghitani
- Department of Neuroscience, University of Wisconsin, Madison, Wisconsin; Neuroscience Training Program, University of Wisconsin, Madison, Wisconsin
| | - Meyer B Jackson
- Department of Neuroscience, University of Wisconsin, Madison, Wisconsin
| | - Michele A Basso
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, The Brain Research Institute, University of California at Los Angeles, Los Angeles, California; and Department of Neurobiology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California
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