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Courcelles EJ, Kjelsberg K, Convertino L, Nair RR, Witter MP, Nigro MJ. Association cortical areas in the mouse contain a large population of fast-spiking GABAergic neurons that do not express parvalbumin. Eur J Neurosci 2024; 59:3236-3255. [PMID: 38643976 DOI: 10.1111/ejn.16341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 03/21/2024] [Accepted: 03/25/2024] [Indexed: 04/23/2024]
Abstract
GABAergic neurons represent 10-15% of the neuronal population of the cortex but exert a powerful control over information flow in cortical circuits. The largest GABAergic class in the neocortex is represented by the parvalbumin-expressing fast-spiking neurons, which provide powerful somatic inhibition to their postsynaptic targets. Recently, the density of parvalbumin interneurons has been shown to be lower in associative areas of the mouse cortex as compared with sensory and motor areas. Modelling work based on these quantifications linked the low-density of parvalbumin interneurons with specific computations of associative cortices. However, it is still unknown whether the total GABAergic population of association cortices is smaller or whether another GABAergic type can compensate for the low density of parvalbumin interneurons. In the present study, we investigated these hypotheses using a combination of neuroanatomy, mouse genetics and neurophysiology. We found that the GABAergic population of association areas is comparable with that of primary sensory areas, and it is enriched of fast-spiking neurons that do not express parvalbumin and were not accounted for by previous quantifications. We developed an intersectional viral strategy to demonstrate that the population of fast-spiking neurons is comparable across cortical regions. Our results provide quantifications of the density of fast-spiking GABAergic neurons and offers new biological constrains to refine current models of cortical computations.
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Affiliation(s)
- Erik Justin Courcelles
- Kavli Institute for Systems Neuroscience, Center for Algorithms in the Cortex, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
| | - Kasper Kjelsberg
- Kavli Institute for Systems Neuroscience, Center for Algorithms in the Cortex, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
| | - Laura Convertino
- Kavli Institute for Systems Neuroscience, Center for Algorithms in the Cortex, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
| | - Rajeevkumar Raveendran Nair
- Kavli Institute for Systems Neuroscience, Center for Algorithms in the Cortex, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
| | - Menno P Witter
- Kavli Institute for Systems Neuroscience, Center for Algorithms in the Cortex, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
| | - Maximiliano José Nigro
- Kavli Institute for Systems Neuroscience, Center for Algorithms in the Cortex, Egil and Pauline Braathen and Fred Kavli Center for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
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Wang R, Zhu W, Liang G, Xu J, Guo J, Wang L. Animal models for epileptic foci localization, seizure detection, and prediction by electrical impedance tomography. WILEY INTERDISCIPLINARY REVIEWS. COGNITIVE SCIENCE 2022; 13:e1619. [PMID: 36093634 DOI: 10.1002/wcs.1619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 07/08/2022] [Accepted: 07/14/2022] [Indexed: 06/15/2023]
Abstract
Surgical resection of lesions and closed-loop suppression are the two main treatment options for patients with refractory epilepsy whose symptoms cannot be managed with medicines. Unfortunately, failures in foci localization and seizure prediction are constraining these treatments. Electrical impedance tomography (EIT), sensitive to impedance changes caused by blood flow or cell swelling, is a potential new way to locate epileptic foci and predict seizures. Animal validation is a necessary research process before EIT can be used in clinical practice, but it is unclear which among the many animal epilepsy models is most suited to this task. The selection of an animal model of epilepsy that is similar to human seizures and can be adapted to EIT is important for the accuracy and reliability of EIT research results. This study provides an overview of the animal models of epilepsy that have been used in research on the use of EIT to locate the foci or predict seizures; discusses the advantages and disadvantages of these models regarding inducement by chemical convulsant and electrical stimulation; and finally proposes optimal animal models of epilepsy to obtain more convincing research results for foci localization and seizure prediction by EIT. The ultimate goal of this study is to facilitate the development of new treatments for patients with refractory epilepsy. This article is categorized under: Neuroscience > Clinical Neuroscience Psychology > Brain Function and Dysfunction.
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Affiliation(s)
- Rong Wang
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
| | - Wenjing Zhu
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
| | - Guohua Liang
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
| | - Jiaming Xu
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
| | - Jie Guo
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
| | - Lei Wang
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
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3
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Kajiwara R, Tominaga T. Perirhinal cortex area 35 controls the functional link between the perirhinal and entorhinal-hippocampal circuitry: D-type potassium channel-mediated gating of neural propagation from the perirhinal cortex to the entorhinal-hippocampal circuitry. Bioessays 2020; 43:e2000084. [PMID: 33236360 DOI: 10.1002/bies.202000084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 10/15/2020] [Accepted: 10/15/2020] [Indexed: 11/07/2022]
Abstract
In several experimental conditions, neuronal excitation at the perirhinal cortex (PC) does not propagate to the entorhinal cortex (EC) due to a "wall" of inhibition, which may help to create functional coupling and un-coupling of the PC and EC in the medial temporal lobe. However, little is known regarding the coupling control process. Herein, we propose that the deep layer of area 35 in the PC plays a pivotal role in opening the gate for coupling, thus allowing the activity in the PC to propagate to the EC. Using voltage-sensitive dye imaging for the brain slices of rodents, we show that a slowly inactivating potassium conductance in this area is essential to induce excitation overtaking the inhibitory control. This coupling between the distinct neural circuits persists for at least 1 h. We elucidate further implications of this network-level plastic behavior and its mechanism.
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Affiliation(s)
- Riichi Kajiwara
- Department of Electronics and Bioinformatics, School of Science and Technology, Meiji University, Kawasaki, Japan
| | - Takashi Tominaga
- Laboratory for Neural Circuit Systems, Institute of Neuroscience, Tokushima Bunri University, Sanuki, Japan
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4
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Cognitive and behavioral effects of brief seizures in mice. Epilepsy Behav 2019; 98:249-257. [PMID: 31398689 DOI: 10.1016/j.yebeh.2019.07.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 07/03/2019] [Accepted: 07/04/2019] [Indexed: 11/22/2022]
Abstract
Comorbidities associated with epilepsy greatly reduce patients' quality of life. Since antiepilepsy drugs show limited success in ameliorating cognitive and behavioral symptoms, there is a need to better understand the mechanisms underlying epilepsy-related cognitive and behavioral impairments. Most prior research addressing this problem has focused on chronic epilepsy, wherein many factors can simultaneously impact cognition and behavior. The purpose of the present study was to develop a testing paradigm using mice that can provide new insight into how short-term biological changes underlying acute seizures impact cognition and behavior. In Experiment 1, naïve C57BL/6J mice were subjected to either three brief, generalized electroconvulsive seizure (ECS) or three sham treatments equally spaced over the course of 30 min. Over the next 2 h, mice were tested in a novel object recognition paradigm. Follow-up studies examined locomotor activity immediately before and after (Experiment 2), immediately after (Experiment 3), and 45 min after (Experiment 4) a set of three ECS or sham treatments. Whereas results demonstrated that there was no statistically significant difference in recognition memory acquisition between ECS and sham-treated mice, measures of anxiety-like behavior were increased and novel object interest was decreased in ECS-treated mice compared with that in sham. Interestingly, ECS also produced a delayed inhibitory effect on locomotion, decreasing open-field activity 45-min posttreatment compared to sham. We conclude that a small cluster of brief seizures can have acute, behaviorally relevant effects in mice, and that greater emphasis should be placed on events that take place before chronic epilepsy is established in order to better understand epilepsy-related cognitive and behavioral impairments. Future research would benefit from using the paradigms defined above to study the effects of individual seizures on mouse cognition and behavior.
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Kajiwara R, Tominaga Y, Tominaga T. Network Plasticity Involved in the Spread of Neural Activity Within the Rhinal Cortices as Revealed by Voltage-Sensitive Dye Imaging in Mouse Brain Slices. Front Cell Neurosci 2019; 13:20. [PMID: 30804757 PMCID: PMC6378919 DOI: 10.3389/fncel.2019.00020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Accepted: 01/16/2019] [Indexed: 11/13/2022] Open
Abstract
The rhinal cortices, such as the perirhinal cortex (PC) and the entorhinal cortex (EC), are located within the bidirectional pathway between the neocortex and the hippocampus. Physiological studies indicate that the perirhinal transmission of neocortical inputs to the EC occurs at an extremely low probability, though many anatomical studies indicated strong connections exist in the pathway. Our previous study in rat brain slices indicated that an increase in excitability in deep layers of the PC/EC border initiated the neural activity transfer from the PC to the EC. In the present study, we hypothesized that such changes in network dynamics are not incidental observations but rather due to the plastic features of the perirhinal network, which links with the EC. To confirm this idea, we analyzed the network properties of neural transmission throughout the rhinal cortices and the plastic behavior of the network by performing a single-photon wide-field optical recording technique with a voltage-sensitive dye (VSD) in mouse brain slices of the PC, the EC, and the hippocampus. The low concentration of 4-aminopyridine (4-AP; 40 μM) enhanced neural activity in the PC, which eventually propagated to the EC via the deep layers of the PC/EC border. Interestingly, washout of 4-AP was unable to reverse entorhinal activation to the previous state. This change in the network property persisted for more than 1 h. This observation was not limited to the application of 4-AP. Burst stimulation to neurons in the perirhinal deep layers also induced the same change of network property. These results indicate the long-lasting modification of physiological connection between the PC and the EC, suggesting the existence of plasticity in the perirhinal-entorhinal network.
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Affiliation(s)
- Riichi Kajiwara
- Department of Electronics and Bioinformatics, School of Science and Technology, Meiji University, Kawasaki, Japan
| | - Yoko Tominaga
- Laboratory for Neural Circuit Systems, Institute of Neuroscience, Tokushima Bunri University, Sanuki, Japan
| | - Takashi Tominaga
- Laboratory for Neural Circuit Systems, Institute of Neuroscience, Tokushima Bunri University, Sanuki, Japan
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Young JC, Vaughan DN, Paolini AG, Jackson GD. Electrical stimulation of the piriform cortex for the treatment of epilepsy: A review of the supporting evidence. Epilepsy Behav 2018; 88:152-161. [PMID: 30269034 DOI: 10.1016/j.yebeh.2018.09.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 09/04/2018] [Accepted: 09/09/2018] [Indexed: 10/28/2022]
Abstract
In this review, we consider how the piriform cortex is engaged in both focal and generalized epilepsy networks and postulate the various neural pathways that can be effectively neuromodulated by stimulation at this site. This highlights the common involvement of the piriform cortex in epilepsy. We address both current and future preclinical studies of deep brain stimulation (DBS) of the piriform cortex, with attention to the critical features of these trials that will enable them to be of greatest utility in informing clinical translation. Although recent DBS trials have utilized thalamic targets, electrical stimulation of the piriform cortex may also be a useful intervention for people with epilepsy. However, more work is required to develop a solid foundation for this approach before considering human trials.
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Affiliation(s)
- James C Young
- The Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, 245 Burgundy Street, Heidelberg, Victoria 3084, Australia; Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne, 30 Royal Parade, Parkville, Victoria 3052, Australia.
| | - David N Vaughan
- The Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, 245 Burgundy Street, Heidelberg, Victoria 3084, Australia; Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne, 30 Royal Parade, Parkville, Victoria 3052, Australia; Department of Neurology, Austin Health, Melbourne, 145 Studley Road, Heidelberg, Victoria 3084, Australia
| | - Antonio G Paolini
- The Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, 245 Burgundy Street, Heidelberg, Victoria 3084, Australia; ISN Psychology - Institute for Social Neuroscience, Melbourne, Level 6/10 Martin Street, Heidelberg, Victoria 3084, Australia; School of Psychology and Public Health, La Trobe University, Melbourne, Plenty Road and Kingsbury Drive, Bundoora, VIC 3068, Australia
| | - Graeme D Jackson
- The Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, 245 Burgundy Street, Heidelberg, Victoria 3084, Australia; Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne, 30 Royal Parade, Parkville, Victoria 3052, Australia; Department of Neurology, Austin Health, Melbourne, 145 Studley Road, Heidelberg, Victoria 3084, Australia
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7
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Voltage-Dependent Calcium Channels, Calcium Binding Proteins, and Their Interaction in the Pathological Process of Epilepsy. Int J Mol Sci 2018; 19:ijms19092735. [PMID: 30213136 PMCID: PMC6164075 DOI: 10.3390/ijms19092735] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 09/06/2018] [Accepted: 09/07/2018] [Indexed: 01/08/2023] Open
Abstract
As an important second messenger, the calcium ion (Ca2+) plays a vital role in normal brain function and in the pathophysiological process of different neurodegenerative diseases including Alzheimer’s disease (AD), Parkinson’s disease (PD), and epilepsy. Ca2+ takes part in the regulation of neuronal excitability, and the imbalance of intracellular Ca2+ is a trigger factor for the occurrence of epilepsy. Several anti-epileptic drugs target voltage-dependent calcium channels (VDCCs). Intracellular Ca2+ levels are mainly controlled by VDCCs located in the plasma membrane, the calcium-binding proteins (CBPs) inside the cytoplasm, calcium channels located on the intracellular calcium store (particular the endoplasmic reticulum/sarcoplasmic reticulum), and the Ca2+-pumps located in the plasma membrane and intracellular calcium store. So far, while many studies have established the relationship between calcium control factors and epilepsy, the mechanism of various Ca2+ regulatory factors in epileptogenesis is still unknown. In this paper, we reviewed the function, distribution, and alteration of VDCCs and CBPs in the central nervous system in the pathological process of epilepsy. The interaction of VDCCs with CBPs in the pathological process of epilepsy was also summarized. We hope this review can provide some clues for better understanding the mechanism of epileptogenesis, and for the development of new anti-epileptic drugs targeting on VDCCs and CBPs.
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8
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Myhrer T, Mariussen E, Aas P. Development of neuropathology following soman poisoning and medical countermeasures. Neurotoxicology 2018; 65:144-165. [DOI: 10.1016/j.neuro.2018.02.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 02/12/2018] [Accepted: 02/14/2018] [Indexed: 01/12/2023]
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Soliman AM, Fathalla AM, Moustafa AA. Adenosine role in brain functions: Pathophysiological influence on Parkinson's disease and other brain disorders. Pharmacol Rep 2018; 70:661-667. [PMID: 29909246 DOI: 10.1016/j.pharep.2018.02.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2017] [Revised: 01/12/2018] [Accepted: 02/01/2018] [Indexed: 12/15/2022]
Abstract
Although adenosine plays a key role in multiple motor, affective, and cognitive processes, it has received less attention in the neuroscience field compared to other neurotransmitters (e.g., dopamine). In this review, we highlight the role of adenosine in behavior as well as its interaction with other neurotransmitters, such as dopamine. We also discuss brain disorders impacted by alterations to adenosine, and how targeting adenosine can ameliorate Parkinson's disease motor symptoms. We also discuss the role of caffeine (as an adenosine antagonist) on cognition as well as a neuroprotective agent against Parkinson's disease (PD).
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Affiliation(s)
- Amira M Soliman
- Department of Pharmacology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt.
| | - Ahmed M Fathalla
- Department of Pharmacology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Ahmed A Moustafa
- Department of Veterans Affairs, New Jersey Health Care System, East Orange, NJ, USA; School of Social Sciences and Psychology and Marcs Institute for Brain and Behaviour, Western Sydney University, Sydney, New South Wales, Australia.
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10
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Willems JGP, Wadman WJ, Cappaert NLM. Parvalbumin interneuron mediated feedforward inhibition controls signal output in the deep layers of the perirhinal-entorhinal cortex. Hippocampus 2018; 28:281-296. [PMID: 29341361 PMCID: PMC5900730 DOI: 10.1002/hipo.22830] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 01/03/2018] [Accepted: 01/08/2018] [Indexed: 11/11/2022]
Abstract
The perirhinal (PER) and lateral entorhinal (LEC) cortex form an anatomical link between the neocortex and the hippocampus. However, neocortical activity is transmitted through the PER and LEC to the hippocampus with a low probability, suggesting the involvement of the inhibitory network. This study explored the role of interneuron mediated inhibition, activated by electrical stimulation in the agranular insular cortex (AiP), in the deep layers of the PER and LEC. Activated synaptic input by AiP stimulation rarely evoked action potentials in the PER‐LEC deep layer excitatory principal neurons, most probably because the evoked synaptic response consisted of a small excitatory and large inhibitory conductance. Furthermore, parvalbumin positive (PV) interneurons—a subset of interneurons projecting onto the axo‐somatic region of principal neurons—received synaptic input earlier than principal neurons, suggesting recruitment of feedforward inhibition. This synaptic input in PV interneurons evoked varying trains of action potentials, explaining the fast rising, long lasting synaptic inhibition received by deep layer principal neurons. Altogether, the excitatory input from the AiP onto deep layer principal neurons is overruled by strong feedforward inhibition. PV interneurons, with their fast, extensive stimulus‐evoked firing, are able to deliver this fast evoked inhibition in principal neurons. This indicates an essential role for PV interneurons in the gating mechanism of the PER‐LEC network.
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Affiliation(s)
- Janske G P Willems
- Center for Neuroscience, Sammerdam Institute for Life Sciences, University of Amsterdam, SciencePark 904, Amsterdam 1098 XH, The Netherlands
| | - Wytse J Wadman
- Center for Neuroscience, Sammerdam Institute for Life Sciences, University of Amsterdam, SciencePark 904, Amsterdam 1098 XH, The Netherlands
| | - Natalie L M Cappaert
- Center for Neuroscience, Sammerdam Institute for Life Sciences, University of Amsterdam, SciencePark 904, Amsterdam 1098 XH, The Netherlands
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11
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Albertini G, Walrave L, Demuyser T, Massie A, De Bundel D, Smolders I. 6 Hz corneal kindling in mice triggers neurobehavioral comorbidities accompanied by relevant changes in c-Fos immunoreactivity throughout the brain. Epilepsia 2017; 59:67-78. [DOI: 10.1111/epi.13943] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/10/2017] [Indexed: 12/23/2022]
Affiliation(s)
- Giulia Albertini
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information; Center for Neurosciences; Vrije Universiteit Brussel; Brussels Belgium
| | - Laura Walrave
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information; Center for Neurosciences; Vrije Universiteit Brussel; Brussels Belgium
| | - Thomas Demuyser
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information; Center for Neurosciences; Vrije Universiteit Brussel; Brussels Belgium
| | - Ann Massie
- Department of Pharmaceutical Biotechnology and Molecular Biology; Center for Neurosciences; Vrije Universiteit Brussel; Brussels Belgium
| | - Dimitri De Bundel
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information; Center for Neurosciences; Vrije Universiteit Brussel; Brussels Belgium
| | - Ilse Smolders
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information; Center for Neurosciences; Vrije Universiteit Brussel; Brussels Belgium
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12
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David LS, Topolnik L. Target-specific alterations in the VIP inhibitory drive to hippocampal GABAergic cells after status epilepticus. Exp Neurol 2017; 292:102-112. [PMID: 28315308 DOI: 10.1016/j.expneurol.2017.03.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 03/08/2017] [Accepted: 03/14/2017] [Indexed: 01/09/2023]
Abstract
Status epilepticus (SE) is associated with complex reorganization of hippocampal circuits involving a significant loss of specific subtypes of GABAergic interneurons. While adaptive circuit plasticity may increase the chances for recruitment of surviving interneurons, the underlying mechanisms remain largely unknown. We studied the alterations in the inhibitory tone received by the hippocampal CA1 oriens/alveus (O/A) interneurons from the vasoactive intestinal peptide (VIP)- and calretinin (CR)-expressing interneurons using the pilocarpine-induced status epilepticus (SE) model of epilepsy. Our data showed that, while the overall density of the VIP/CR-co-expressing interneurons remained preserved, the number of axonal boutons made by these cells within the CA1 O/A was significantly lower after SE. Furthermore, VIP/CR interneurons exhibited significant alterations in their dendritic morphology and passive membrane properties. Subsequently, while all O/A interneuron types, including oriens-lacunosum moleculare (OLM), bistratified (Bis) and basket cells, exhibited decrease in spontaneous inhibitory drive, Bis and basket cells showed a smaller amplitude of light-evoked IPSCs mediated by the selective activation of VIP-positive interneurons. These data point to the target cell-specific changes in the inhibitory tone provided by the VIP cells to O/A interneurons following SE. Given that basket, Bis and OLM cells coordinate different subcellular domains of pyramidal neurons, significant disinhibition of basket and Bis cells along with a previously reported loss of the OLMs may result in a redistribution of inhibition converging onto pyramidal neurons, with a direct impact onto their recruitment to epileptiform network activity and seizure propagation.
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Affiliation(s)
- Linda Suzanne David
- Neuroscience Axis, CHU de Québec Research Center, Department of Biochemistry, Microbiology and Bio-informatics, Laval University, Québec, PQ, Canada
| | - Lisa Topolnik
- Neuroscience Axis, CHU de Québec Research Center, Department of Biochemistry, Microbiology and Bio-informatics, Laval University, Québec, PQ, Canada.
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13
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Barros-Barbosa AR, Ferreirinha F, Oliveira Â, Mendes M, Lobo MG, Santos A, Rangel R, Pelletier J, Sévigny J, Cordeiro JM, Correia-de-Sá P. Adenosine A 2A receptor and ecto-5'-nucleotidase/CD73 are upregulated in hippocampal astrocytes of human patients with mesial temporal lobe epilepsy (MTLE). Purinergic Signal 2016; 12:719-734. [PMID: 27650530 PMCID: PMC5124012 DOI: 10.1007/s11302-016-9535-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 09/05/2016] [Indexed: 12/11/2022] Open
Abstract
Refractoriness to existing medications of up to 80 % of the patients with mesial temporal lobe epilepsy (MTLE) prompts for finding new antiepileptic drug targets. The adenosine A2A receptor emerges as an interesting pharmacological target since its excitatory nature partially counteracts the dominant antiepileptic role of endogenous adenosine acting via inhibitory A1 receptors. Gain of function of the excitatory A2A receptor has been implicated in a significant number of brain pathologies commonly characterized by neuronal excitotoxicity. Here, we investigated changes in the expression and cellular localization of the A2A receptor and of the adenosine-generating enzyme, ecto-5'-nucleotidase/CD73, in the hippocampus of control individuals and MTLE human patients. Western blot analysis indicates that the A2A receptor is more abundant in the hippocampus of MTLE patients compared to control individuals. Immunoreactivity against the A2A receptor predominates in astrocytes staining positively for the glial fibrillary acidic protein (GFAP). No co-localization was observed between the A2A receptor and neuronal cell markers, like synaptotagmin 1/2 (nerve terminals) and neurofilament 200 (axon fibers). Hippocampal astrogliosis observed in MTLE patients was accompanied by a proportionate increase in A2A receptor and ecto-5'-nucleotidase/CD73 immunoreactivities. Given our data, we hypothesize that selective blockade of excessive activation of astrocytic A2A receptors and/or inhibition of surplus adenosine formation by membrane-bound ecto-5'-nucleotidase/CD73 may reduce neuronal excitability, thus providing a novel therapeutic target for drug-refractory seizures in MTLE patients.
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Affiliation(s)
- Aurora R Barros-Barbosa
- Laboratório de Farmacologia e Neurobiologia-Center for Drug Discovery and Innovative Medicines (MedInUP), Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), R. Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal
| | - Fátima Ferreirinha
- Laboratório de Farmacologia e Neurobiologia-Center for Drug Discovery and Innovative Medicines (MedInUP), Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), R. Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal
| | - Ângela Oliveira
- Laboratório de Farmacologia e Neurobiologia-Center for Drug Discovery and Innovative Medicines (MedInUP), Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), R. Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal
| | - Marina Mendes
- Laboratório de Farmacologia e Neurobiologia-Center for Drug Discovery and Innovative Medicines (MedInUP), Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), R. Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal
| | - M Graça Lobo
- Laboratório de Farmacologia e Neurobiologia-Center for Drug Discovery and Innovative Medicines (MedInUP), Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), R. Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal
| | - Agostinho Santos
- Serviço de Patologia Forense, Instituto Nacional de Medicina Legal e Ciências Forenses-Delegação do Norte (INMLCF-DN), Porto, Portugal
| | - Rui Rangel
- Serviço de Neurocirurgia, Centro Hospitalar do Porto-Hospital Geral de Santo António (CHP-HGSA), Porto, Portugal
| | - Julie Pelletier
- Centre de Recherche du CHU de Québec-Université Laval, CHUL, QC, Québec, Canada
| | - Jean Sévigny
- Centre de Recherche du CHU de Québec-Université Laval, CHUL, QC, Québec, Canada
- Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médicine, Université Laval, QC, Québec, Canada
| | - J Miguel Cordeiro
- Laboratório de Farmacologia e Neurobiologia-Center for Drug Discovery and Innovative Medicines (MedInUP), Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), R. Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal
| | - Paulo Correia-de-Sá
- Laboratório de Farmacologia e Neurobiologia-Center for Drug Discovery and Innovative Medicines (MedInUP), Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), R. Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal.
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14
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Avoli M, de Curtis M, Gnatkovsky V, Gotman J, Köhling R, Lévesque M, Manseau F, Shiri Z, Williams S. Specific imbalance of excitatory/inhibitory signaling establishes seizure onset pattern in temporal lobe epilepsy. J Neurophysiol 2016; 115:3229-37. [PMID: 27075542 DOI: 10.1152/jn.01128.2015] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 04/06/2016] [Indexed: 11/22/2022] Open
Abstract
Low-voltage fast (LVF) and hypersynchronous (HYP) patterns are the seizure-onset patterns most frequently observed in intracranial EEG recordings from mesial temporal lobe epilepsy (MTLE) patients. Both patterns also occur in models of MTLE in vivo and in vitro, and these studies have highlighted the predominant involvement of distinct neuronal network/neurotransmitter receptor signaling in each of them. First, LVF-onset seizures in epileptic rodents can originate from several limbic structures, frequently spread, and are associated with high-frequency oscillations in the ripple band (80-200 Hz), whereas HYP onset seizures initiate in the hippocampus and tend to remain focal with predominant fast ripples (250-500 Hz). Second, in vitro intracellular recordings from principal cells in limbic areas indicate that pharmacologically induced seizure-like discharges with LVF onset are initiated by a synchronous inhibitory event or by a hyperpolarizing inhibitory postsynaptic potential barrage; in contrast, HYP onset is associated with a progressive impairment of inhibition and concomitant unrestrained enhancement of excitation. Finally, in vitro optogenetic experiments show that, under comparable experimental conditions (i.e., 4-aminopyridine application), the initiation of LVF- or HYP-onset seizures depends on the preponderant involvement of interneuronal or principal cell networks, respectively. Overall, these data may provide insight to delineate better therapeutic targets in the treatment of patients presenting with MTLE and, perhaps, with other epileptic disorders as well.
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Affiliation(s)
- Massimo Avoli
- Montreal Neurological Institute and Departments of Neurology & Neurosurgery and of Physiology, McGill University, Montréal, Québec, Canada; Facoltà di Medicina e Odontoiatria, Sapienza Università di Roma, Rome, Italy;
| | - Marco de Curtis
- Epilepsy Unit, Fondazione Istituto Neurologico Carlo Besta, Milan, Italy
| | - Vadym Gnatkovsky
- Epilepsy Unit, Fondazione Istituto Neurologico Carlo Besta, Milan, Italy
| | - Jean Gotman
- Montreal Neurological Institute and Departments of Neurology & Neurosurgery and of Physiology, McGill University, Montréal, Québec, Canada
| | - Rüdiger Köhling
- Oscar-Langendorff-Institute of Physiology, Rostock University Medical Center, Rostock, Germany; and
| | - Maxime Lévesque
- Montreal Neurological Institute and Departments of Neurology & Neurosurgery and of Physiology, McGill University, Montréal, Québec, Canada
| | - Frédéric Manseau
- Douglas Mental Health University Institute, McGill University, Montréal, Québec, Canada
| | - Zahra Shiri
- Montreal Neurological Institute and Departments of Neurology & Neurosurgery and of Physiology, McGill University, Montréal, Québec, Canada
| | - Sylvain Williams
- Douglas Mental Health University Institute, McGill University, Montréal, Québec, Canada
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15
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Wang X, Song X, Wu L, Nadler JV, Zhan RZ. Persistent Hyperactivity of Hippocampal Dentate Interneurons After a Silent Period in the Rat Pilocarpine Model of Epilepsy. Front Cell Neurosci 2016; 10:94. [PMID: 27092056 PMCID: PMC4824773 DOI: 10.3389/fncel.2016.00094] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 03/24/2016] [Indexed: 12/15/2022] Open
Abstract
Profile of GABAergic interneuron activity after pilocarpine-induced status epilepticus (SE) was examined in the rat hippocampal dentate gyrus by analyzing immediate early gene expression and recording spontaneous firing at near resting membrane potential (REM). SE for exact 2 h or more than 2 h was induced in the male Sprague-Dawley rats by an intraperitoneal injection of pilocarpine. Expression of immediate early genes (IEGs) was examined at 1 h, 1 week, 2 weeks or more than 10 weeks after SE. For animals to be examined at 1 h after SE, SE lasted for exact 2 h was terminated by an intraperitoneal injection of diazepam. Spontaneous firing at near the REM was recorded in interneurons located along the border between the granule cell layer and the hilus more than 10 weeks after SE. Results showed that both c-fos and activity-regulated cytoskeleton associated protein (Arc) in hilar GABAergic interneurons were up-regulated after SE in a biphasic manner; they were increased at 1 h and more than 2 weeks, but not at 1 week after SE. Ten weeks after SE, nearly 60% of hilar GABAergic cells expressed c-fos. With the exception of calretinin (CR)-positive cells, percentages of hilar neuronal nitric oxide synthase (nNOS)-, neuropeptide Y (NPY)-, parvalbumin (PV)-, and somatostatin (SOM)-positive cells with c-fos expression are significantly higher than those of controls more than 10 weeks after SE. Without the REM to be more depolarizing and changed threshold potential level in SE-induced rats, cell-attached recording revealed that nearly 90% of hilar interneurons fired spontaneously at near the REM while only 22% of the same cell population did so in the controls. In conclusion, pilocarpine-induced SE eventually leads to a state in which surviving dentate GABAergic interneurons become hyperactive with a subtype-dependent manner; this implies that a fragile balance between excitation and inhibition exists in the dentate gyrus and in addition, the activity-dependent up-regulation of IEGs may underlie plastic changes seen in some types of GABAergic cells in the pilocarpine model of epilepsy.
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Affiliation(s)
- Xiaochen Wang
- Department of Physiology, Shandong University School of Medicine Jinan, China
| | - Xinyu Song
- Department of Respiratory Medicine, Affiliated Hospital of Binzhou Medical University Binzhou, Shandong, China
| | - Lin Wu
- Department of Physiology, Shandong University School of Medicine Jinan, China
| | - J Victor Nadler
- Department of Pharmacology and Cancer Biology, Duke University Medical Center Durham, NC, USA
| | - Ren-Zhi Zhan
- Department of Physiology, Shandong University School of Medicine Jinan, China
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16
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Hypersynchronous ictal onset in the perirhinal cortex results from dynamic weakening in inhibition. Neurobiol Dis 2015; 87:1-10. [PMID: 26699817 DOI: 10.1016/j.nbd.2015.12.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Revised: 11/23/2015] [Accepted: 12/10/2015] [Indexed: 11/23/2022] Open
Abstract
We obtained field, K(+) selective and "sharp" intracellular recordings from the rat entorhinal (EC) and perirhinal (PC) cortices in an in vitro brain slice preparation to identify the events occurring at interictal-to-ictal transition during 4-aminopyridine application. Field recordings revealed interictal- (duration: 1.1 to 2.2s) and ictal-like (duration: 31 to 103s) activity occurring synchronously in EC and PC; in addition, interictal spiking in PC increased in frequency shortly before the onset of ictal oscillatory activity thus resembling the hypersynchronous seizure onset seen in epileptic patients and in in vivo animal models. Intracellular recordings with K-acetate+QX314-filled pipettes in PC principal cells showed that spikes at ictal onset had post-burst hyperpolarizations (presumably mediated by postsynaptic GABAA receptors), which gradually decreased in amplitude. This trend was associated with a progressive positive shift of the post-burst hyperpolarization reversal potential. Finally, the transient elevations in [K(+)]o (up to 4.4mM from a base line of 3.2mM) - which occurred with the interictal events in PC - progressively increased (up to 7.3mM) with the spike immediately preceding ictal onset. Our findings indicate that hypersynchronous seizure onset in rat PC is caused by dynamic weakening of GABAA receptor signaling presumably resulting from [K(+)]o accumulation.
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17
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Weiss AR, Bachevalier J. Object and spatial memory after neonatal perirhinal lesions in monkeys. Behav Brain Res 2015; 298:210-7. [PMID: 26593109 DOI: 10.1016/j.bbr.2015.11.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 11/02/2015] [Accepted: 11/09/2015] [Indexed: 12/19/2022]
Abstract
The contribution of the perirhinal cortex (PRh) to recognition memory is well characterized in adults, yet the same lesions have limited effect on recognition of spatial locations. Here, we assessed whether the same outcomes will follow when perirhinal lesions are performed in infancy. Monkeys with neonatal perirhinal (Neo-PRh) lesions and control animals were tested in three operant recognition tasks as they reached adulthood: Delayed Nonmatching-to-Sample (DNMS) and Object Memory Span (OMS), measuring object recognition, and Spatial Memory Span (SMS), measuring recognition of spatial locations. Although Neo-PRh lesions did not impact acquisition of the DNMS rule, they did impair performance when the delays were extended from 30s to 600s. In contrast, the same neonatal lesions had no impact on either the object or spatial memory span tasks, suggesting that the lesions impacted the maintenance of information across longer delays and not memory capacity. Finally, the magnitude of recognition memory impairment after the Neo-PRh lesions was similar to that previously observed after adult-onset perirhinal lesions, indicating minimal, or no, functional compensation after the early PRh lesions. Overall, the results indicate that the PRh is a cortical structure that is important for the normal development of mechanisms supporting object recognition memory. Its contribution may be relevant to the memory impairment observed with human cases of temporal lobe epilepsy without hippocampal sclerosis, but not to the memory impairment found in developmental amnesia cases.
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Affiliation(s)
| | - Jocelyne Bachevalier
- Emory University, Georgia; Yerkes National Primate Research Center, Atlanta, Georgia
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18
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Kano T, Inaba Y, D'Antuono M, Biagini G, Levésque M, Avoli M. Blockade of in vitro ictogenesis by low-frequency stimulation coincides with increased epileptiform response latency. J Neurophysiol 2015; 114:21-8. [PMID: 25925325 PMCID: PMC4493663 DOI: 10.1152/jn.00248.2015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 04/29/2015] [Indexed: 11/22/2022] Open
Abstract
Low-frequency stimulation, delivered through transcranial magnetic or deep-brain electrical procedures, reduces seizures in patients with pharmacoresistant epilepsy. A similar control of ictallike discharges is exerted by low-frequency electrical stimulation in rodent brain slices maintained in vitro during convulsant treatment. By employing field and "sharp" intracellular recordings, we analyzed here the effects of stimuli delivered at 0.1 or 1 Hz in the lateral nucleus of the amygdala on ictallike epileptiform discharges induced by the K(+) channel blocker 4-aminopyridine in the perirhinal cortex, in a rat brain slice preparation. We found that 1) ictal events were nominally abolished when the stimulus rate was brought from 0.1 to 1 Hz; 2) this effect was associated with an increased latency of the epileptiform responses recorded in perirhinal cortex following each stimulus; and 3) both changes recovered to control values following arrest of the 1-Hz stimulation protocol. The control of ictal activity by 1-Hz stimulation and the concomitant latency increase were significantly reduced by GABAB receptor antagonism. We propose that this frequency-dependent increase in latency represents a short-lasting, GABAB receptor-dependent adaptive mechanism that contributes to decrease epileptiform synchronization, thus blocking seizures in epileptic patients and animal models.
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Affiliation(s)
- Toshiyuki Kano
- Montreal Neurological Institute and Departments of Neurology & Neurosurgery and Physiology, McGill University, Montreal, Quebec, Canada
| | - Yuji Inaba
- Montreal Neurological Institute and Departments of Neurology & Neurosurgery and Physiology, McGill University, Montreal, Quebec, Canada; Shinshu University, School of Medicine, Matsumoto, Japan; and
| | - Margherita D'Antuono
- Montreal Neurological Institute and Departments of Neurology & Neurosurgery and Physiology, McGill University, Montreal, Quebec, Canada
| | - Giuseppe Biagini
- Montreal Neurological Institute and Departments of Neurology & Neurosurgery and Physiology, McGill University, Montreal, Quebec, Canada; Dipartimento di Scienze Biomediche, Metaboliche e Neuroscienze, Università di Modena e Reggio Emilia, Modena, Italy
| | - Maxime Levésque
- Montreal Neurological Institute and Departments of Neurology & Neurosurgery and Physiology, McGill University, Montreal, Quebec, Canada
| | - Massimo Avoli
- Montreal Neurological Institute and Departments of Neurology & Neurosurgery and Physiology, McGill University, Montreal, Quebec, Canada;
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19
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Adams C, Adams NE, Traub RD, Whittington MA. Electrographic waveform structure predicts laminar focus location in a model of temporal lobe seizures in vitro. PLoS One 2015; 10:e0121676. [PMID: 25799020 PMCID: PMC4370580 DOI: 10.1371/journal.pone.0121676] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 02/03/2015] [Indexed: 11/20/2022] Open
Abstract
Temporal lobe epilepsy is the most common form of partial-onset epilepsy and accounts for the majority of adult epilepsy cases in most countries. A critical role for the hippocampus (and to some extent amygdala) in the pathology of these epilepsies is clear, with selective removal of these regions almost as effective as temporal lobectomy in reducing subsequent seizure risk. However, there is debate about whether hippocampus is 'victim' or 'perpetrator': The structure is ideally placed to 'broadcast' epileptiform activity to a great many other brain regions, but removal often leaves epileptiform events still occurring in cortex, particularly in adjacent areas, and recruitment of the hippocampus into seizure-like activity has been shown to be difficult in clinically-relevant models. Using a very simple model of acute epileptiform activity with known, single primary pathology (GABAA Receptor partial blockade), we track the onset and propagation of epileptiform events in hippocampus, parahippocampal areas and neocortex. In this model the hippocampus acts as a potential seizure focus for the majority of observed events. Events with hippocampal focus were far more readily propagated throughout parahippocampal areas and into neocortex than vice versa. The electrographic signature of events of hippocampal origin was significantly different to those of primary neocortical origin - a consequence of differential laminar activation. These data confirm the critical role of the hippocampus in epileptiform activity generation in the temporal lobe and suggest the morphology of non-invasive electrical recording of neocortical interictal events may be useful in confirming this role.
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Affiliation(s)
- Christopher Adams
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Natalie E. Adams
- Hull York Medical School, The University of York, York, United Kingdom
| | - Roger D. Traub
- Dept. Physical Sciences, IBM TJ Watson Research Center, New York, New York, United States of America
- Department of Neurology, Columbia University, New York, New York, United States of America
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20
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Biagini G, D'Antuono M, Inaba Y, Kano T, Ragsdale D, Avoli M. Activity-dependent changes in excitability of perirhinal cortex networks in vitro. Pflugers Arch 2014; 467:805-16. [PMID: 24903241 DOI: 10.1007/s00424-014-1545-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 05/12/2014] [Accepted: 05/26/2014] [Indexed: 11/28/2022]
Abstract
Rat brain slices comprising the perirhinal cortex (PC) and a portion of the lateral nucleus of the amygdala (LA), in standard medium, can generate synchronous oscillatory activity that is associated with action potential discharge and reflects the activation of glutamatergic and GABAergic receptors. We report here that similar synchronous oscillatory events are recorded in the PC in response to single-shock, electrical stimuli delivered in LA. In addition, we found that the latency of these responses progressively increased when the stimulus interval was varied from 10 to 1 s; for example, the response latency during stimuli delivered at 1 Hz was more than twofold longer than that seen during stimulation at 0.1 Hz. This prolongation in latency occurred after approximately 5 stimuli, attained a steady value after 24-35 stimuli, and recovered to control values 30 s after stimulation arrest. These frequency-dependent changes in latency continued to occur during NMDA receptor antagonism but weakened following application of GABAA and/or GABAB receptor blockers. Our findings identify a new type of short-term plasticity that is mediated by GABA receptor function and may play a role in decreasing neuronal network synchronization during repeated activation. We propose that this frequency-dependent adaptive mechanism influences the excitability of limbic networks, thus potentially controlling epileptiform synchronization.
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Affiliation(s)
- Giuseppe Biagini
- Montreal Neurological Institute, McGill University, 3801 Rue University, Montreal, QC, H3A 2B4, Canada
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21
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Di Maio R. Neuronal mechanisms of epileptogenesis. Front Cell Neurosci 2014; 8:29. [PMID: 24600345 PMCID: PMC3930862 DOI: 10.3389/fncel.2014.00029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 02/03/2014] [Indexed: 11/23/2022] Open
Affiliation(s)
- Roberto Di Maio
- Department of Neurology, Pittsburgh Institute for Neurodegenerative Disease, Ri.MED Foundation, University of Pittsburgh Pittsburgh, PA, USA
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