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Kalogeropoulos K, Psarropoulou C. Immature Status Epilepticus Alters the Temporal Relationship between Hippocampal Interictal Epileptiform Discharges and High-frequency Oscillations. Neuroscience 2024; 543:108-120. [PMID: 38401712 DOI: 10.1016/j.neuroscience.2024.02.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 02/16/2024] [Accepted: 02/20/2024] [Indexed: 02/26/2024]
Abstract
The aim was to investigate the long-term effects of a single episode of immature Status Epilepticus (SE) on the excitability of the septal and temporal hippocampus in vitro, by studying the relationship between interictal-like epileptiform discharges (IEDs) and high-frequency oscillations (HFOs; Ripples, Rs and Fast Ripples, FRs). A pentylenetetrazol-induced Status Epilepticus-(SE)-like generalized seizure was induced at postnatal day 20 in 22 male and female juvenile rats, sacrificed >40 days later to prepare hippocampal slices. Spontaneous IEDs induced by Mg2+-free ACSF were recorded from the CA3 area of temporal (T) or septal (S) slices. Recordings were band-pass filtered off-line revealing Rs and FRs and a series of measurements were conducted, with mean values compared with those obtained from age-matched controls (CTRs). In CTR S (vs T) slices, we recorded longer R & FR durations, a longer HFO-IED temporal overlap, higher FR peak power and more frequent FR initiation preceding IEDs (% events). Post-SE, in T slices all types of events duration (IED, R, FR) and the time lag between their onsets (R-IED, FR-IED, R-FR) increased, while FR/R peak power decreased; in S slices, the IED 1st population spike and the FR amplitudes, the R and FR peak power and the (percent) events where Rs or FRs preceded IEDs all decreased. The CA3 IED-HFO relationship offers insights to the septal-to-temporal synchronization patterns; its post-juvenile-SE changes indicate permanent modifications in the septotemporal excitability gradient. Moreover, these findings are in line to region-specific regulation of various currents post-SE, as reported in literature.
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Affiliation(s)
- Konstantinos Kalogeropoulos
- Laboratory of Animal and Human Physiology, Department of Biological Applications and Technology, Faculty of Health Sciences, University of Ioannina, 45110, Greece.
| | - Caterina Psarropoulou
- Laboratory of Animal and Human Physiology, Department of Biological Applications and Technology, Faculty of Health Sciences, University of Ioannina, 45110, Greece.
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Müller S, Kartheus M, Hendinger E, Hübner DC, Schnell E, Rackow S, Bertsche A, Köhling R, Kirschstein T. Persistent Kv7.2/7.3 downregulation in the rat pilocarpine model of mesial temporal lobe epilepsy. Epilepsy Res 2024; 200:107296. [PMID: 38219422 DOI: 10.1016/j.eplepsyres.2024.107296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 12/04/2023] [Accepted: 01/05/2024] [Indexed: 01/16/2024]
Abstract
Mutations within the Kv7.2 and Kv7.3 genes are well described causes for genetic childhood epilepsies. Knowledge on these channels in acquired focal epilepsy, especially in mesial temporal lobe epilepsy (mTLE), however, is scarce. Here, we used the rat pilocarpine model of drug-resistant mTLE to elucidate both expression and function by quantitative polymerase-chain reaction, immunohistochemistry, and electrophysiology, respectively. We found transcriptional downregulation of Kv7.2 and Kv7.3 as well as reduced Kv7.2 expression in epileptic CA1. Consequences were altered synaptic transmission, hyperexcitability which consisted of epileptiform afterpotentials, and increased susceptibility to acute GABAergic disinhibition. Importantly, blocking Kv7 channels with XE991 increased hyperexcitability in control tissue, but not in chronically epileptic tissue suggesting that the Kv7 deficit had precluded XE991 effects in this tissue. Conversely, XE991 resulted in comparable reduction of the paired-pulse ratio in both experimental groups implying preserved presynaptic Kv7.2 function of Schaffer collateral terminals. Consistent with Kv7.2/7.3 downregulation, the Kv7.3 channel opener β-hydroxybutyrate failed to mitigate hyperexcitability. Our findings demonstrate that compromised Kv7 function is not only relevant in genetic epilepsy, but also in acquired focal epilepsy. Moreover, they help explain reduced anti-seizure efficacy of Kv7 channel openers in drug-resistant epilepsy.
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Affiliation(s)
- Steffen Müller
- Oscar Langendorff Institute of Physiology, University Medicine Rostock, Germany
| | - Mareike Kartheus
- Oscar Langendorff Institute of Physiology, University Medicine Rostock, Germany
| | - Elisabeth Hendinger
- Oscar Langendorff Institute of Physiology, University Medicine Rostock, Germany
| | | | - Emma Schnell
- Oscar Langendorff Institute of Physiology, University Medicine Rostock, Germany
| | - Simone Rackow
- Oscar Langendorff Institute of Physiology, University Medicine Rostock, Germany
| | - Astrid Bertsche
- Department Neuropaediatrics, Hospital for Children and Adolescents, University Medicine Greifswald, Germany
| | - Rüdiger Köhling
- Oscar Langendorff Institute of Physiology, University Medicine Rostock, Germany; Center of Transdisciplinary Neurosciences Rostock (CTNR), University Medicine Rostock, Germany
| | - Timo Kirschstein
- Oscar Langendorff Institute of Physiology, University Medicine Rostock, Germany; Center of Transdisciplinary Neurosciences Rostock (CTNR), University Medicine Rostock, Germany.
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Tilelli CQ, Flôres LR, Cota VR, Castro OWD, Garcia-Cairasco N. Amygdaloid complex anatomopathological findings in animal models of status epilepticus. Epilepsy Behav 2021; 121:106831. [PMID: 31864944 DOI: 10.1016/j.yebeh.2019.106831] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 11/15/2019] [Accepted: 11/25/2019] [Indexed: 12/13/2022]
Abstract
Temporal lobe epileptic seizures are one of the most common and well-characterized types of epilepsies. The current knowledge on the pathology of temporal lobe epilepsy relies strongly on studies of epileptogenesis caused by experimentally induced status epilepticus (SE). Although several temporal lobe structures have been implicated in the epileptogenic process, the hippocampal formation is the temporal lobe structure studied in the greatest amount and detail. However, studies in human patients and animal models of temporal lobe epilepsy indicate that the amygdaloid complex can be also an important seizure generator, and several pathological processes have been shown in the amygdala during epileptogenesis. Therefore, in the present review, we systematically selected, organized, described, and analyzed the current knowledge on anatomopathological data associated with the amygdaloid complex during SE-induced epileptogenesis. Amygdaloid complex participation in the epileptogenic process is evidenced, among others, by alterations in energy metabolism, circulatory, and fluid regulation, neurotransmission, immediate early genes expression, tissue damage, cell suffering, inflammation, and neuroprotection. We conclude that major efforts should be made in order to include the amygdaloid complex as an important target area for evaluation in future research on SE-induced epileptogenesis. This article is part of the Special Issue "NEWroscience 2018".
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Affiliation(s)
- Cristiane Queixa Tilelli
- Laboratory of Physiology, Campus Centro-Oeste Dona Lindu, Universidade Federal de São João del-Rei, Av. Sebastião Gonçalves Coelho, 400, Bairro Belvedere, Divinópolis, MG 35.501-296, Brazil.
| | - Larissa Ribeiro Flôres
- Laboratory of Physiology, Campus Centro-Oeste Dona Lindu, Universidade Federal de São João del-Rei, Av. Sebastião Gonçalves Coelho, 400, Bairro Belvedere, Divinópolis, MG 35.501-296, Brazil
| | - Vinicius Rosa Cota
- Laboratory of Neuroengineering and Neuroscience (LINNce), Department of Electrical Engineering, Campus Santo Antônio, Universidade Federal de São João del-Rei, Praça Frei Orlando, 170, Centro, São João Del Rei, MG 36307-352, Brazil
| | - Olagide Wagner de Castro
- Institute of Biological Sciences and Health, Campus A. C. Simões, Universidade Federal de Alagoas, Av. Lourival Melo Mota, s/n, Tabuleiro do Martins, Maceió, AL 57072-970, Brazil
| | - Norberto Garcia-Cairasco
- Neurophysiology and Experimental Neuroethology Laboratory (LNNE), Department of Physiology, School of Medicine, Universidade de São Paulo, Av. Bandeirantes, 3900, Monte Alegre, Ribeirão Preto, SP 14049-900, Brazil.
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Immature Status Epilepticus: In Vitro Models Reveal Differences in Cholinergic Control and HFO Properties of Adult CA3 Interictal Discharges in Temporal vs Septal Hippocampus. Neuroscience 2018; 369:386-398. [DOI: 10.1016/j.neuroscience.2017.11.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 10/30/2017] [Accepted: 11/16/2017] [Indexed: 01/31/2023]
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McGuier NS, Griffin WC, Gass JT, Padula AE, Chesler EJ, Mulholland PJ. Kv7 channels in the nucleus accumbens are altered by chronic drinking and are targets for reducing alcohol consumption. Addict Biol 2016; 21:1097-1112. [PMID: 26104325 DOI: 10.1111/adb.12279] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Alcohol use disorders (AUDs) are a major public health issue and produce enormous societal and economic burdens. Current Food and Drug Administration (FDA)-approved pharmacotherapies for treating AUDs suffer from deleterious side effects and are only effective in a subset of individuals. It is therefore essential to find improved medications for the management of AUDs. Emerging evidence suggests that anticonvulsants are a promising class of drugs for treating individuals with AUDs. In these studies, we used integrative functional genomics to demonstrate that genes that encode Kv7 channels (i.e. Kcnq2/3) are related to alcohol (ethanol) consumption, preference and acceptance in rodents. We then tested the ability of the FDA-approved anticonvulsant retigabine, a Kv7 channel opener, to reduce voluntary ethanol consumption of Wistar rats in a two-bottle choice intermittent alcohol access paradigm. Systemic administration and microinjections of retigabine into the nucleus accumbens significantly reduced alcohol drinking, and retigabine was more effective at reducing intake in high- versus low-drinking populations of Wistar rats. Prolonged voluntary drinking increased the sensitivity to the proconvulsant effects of pharmacological blockade of Kv7 channels and altered surface trafficking and SUMOylation patterns of Kv7.2 channels in the nucleus accumbens. These data implicate Kcnq2/3 in the regulation of ethanol drinking and demonstrate that long-term drinking produces neuroadaptations in Kv7 channels. In addition, these results have identified retigabine as a potential pharmacotherapy for treating AUDs and Kv7 channels as a novel therapeutic target for reducing heavy drinking.
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Affiliation(s)
- Natalie S. McGuier
- Department of Neuroscience; Medical University of South Carolina; Charleston SC USA
| | - William C. Griffin
- Department of Psychiatry and Behavioral Sciences; Medical University of South Carolina; Charleston SC USA
| | - Justin T. Gass
- Department of Neuroscience; Medical University of South Carolina; Charleston SC USA
| | - Audrey E. Padula
- Department of Neuroscience; Medical University of South Carolina; Charleston SC USA
| | | | - Patrick J. Mulholland
- Department of Neuroscience; Medical University of South Carolina; Charleston SC USA
- Department of Psychiatry and Behavioral Sciences; Medical University of South Carolina; Charleston SC USA
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Abstract
This review attempts to give a concise and up-to-date overview on the role of potassium channels in epilepsies. Their role can be defined from a genetic perspective, focusing on variants and de novo mutations identified in genetic studies or animal models with targeted, specific mutations in genes coding for a member of the large potassium channel family. In these genetic studies, a demonstrated functional link to hyperexcitability often remains elusive. However, their role can also be defined from a functional perspective, based on dynamic, aggravating, or adaptive transcriptional and posttranslational alterations. In these cases, it often remains elusive whether the alteration is causal or merely incidental. With ∼80 potassium channel types, of which ∼10% are known to be associated with epilepsies (in humans) or a seizure phenotype (in animals), if genetically mutated, a comprehensive review is a challenging endeavor. This goal may seem all the more ambitious once the data on posttranslational alterations, found both in human tissue from epilepsy patients and in chronic or acute animal models, are included. We therefore summarize the literature, and expand only on key findings, particularly regarding functional alterations found in patient brain tissue and chronic animal models.
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Affiliation(s)
- Rüdiger Köhling
- Oscar Langendorff Institute of Physiology, University of Rostock, Rostock 18057, Germany
| | - Jakob Wolfart
- Oscar Langendorff Institute of Physiology, University of Rostock, Rostock 18057, Germany
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Wolfart J, Laker D. Homeostasis or channelopathy? Acquired cell type-specific ion channel changes in temporal lobe epilepsy and their antiepileptic potential. Front Physiol 2015; 6:168. [PMID: 26124723 PMCID: PMC4467176 DOI: 10.3389/fphys.2015.00168] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 05/19/2015] [Indexed: 01/16/2023] Open
Abstract
Neurons continuously adapt the expression and functionality of their ion channels. For example, exposed to chronic excitotoxicity, neurons homeostatically downscale their intrinsic excitability. In contrast, the “acquired channelopathy” hypothesis suggests that proepileptic channel characteristics develop during epilepsy. We review cell type-specific channel alterations under different epileptic conditions and discuss the potential of channels that undergo homeostatic adaptations, as targets for antiepileptic drugs (AEDs). Most of the relevant studies have been performed on temporal lobe epilepsy (TLE), a widespread AED-refractory, focal epilepsy. The TLE patients, who undergo epilepsy surgery, frequently display hippocampal sclerosis (HS), which is associated with degeneration of cornu ammonis subfield 1 pyramidal cells (CA1 PCs). Although the resected human tissue offers insights, controlled data largely stem from animal models simulating different aspects of TLE and other epilepsies. Most of the cell type-specific information is available for CA1 PCs and dentate gyrus granule cells (DG GCs). Between these two cell types, a dichotomy can be observed: while DG GCs acquire properties decreasing the intrinsic excitability (in TLE models and patients with HS), CA1 PCs develop channel characteristics increasing intrinsic excitability (in TLE models without HS only). However, thorough examination of data on these and other cell types reveals the coexistence of protective and permissive intrinsic plasticity within neurons. These mechanisms appear differentially regulated, depending on the cell type and seizure condition. Interestingly, the same channel molecules that are upregulated in DG GCs during HS-related TLE, appear as promising targets for future AEDs and gene therapies. Hence, GCs provide an example of homeostatic ion channel adaptation which can serve as a primer when designing novel anti-epileptic strategies.
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Affiliation(s)
- Jakob Wolfart
- Oscar Langendorff Institute of Physiology, University of Rostock Rostock, Germany
| | - Debora Laker
- Oscar Langendorff Institute of Physiology, University of Rostock Rostock, Germany
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Are alterations in transmitter receptor and ion channel expression responsible for epilepsies? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 813:211-29. [PMID: 25012379 DOI: 10.1007/978-94-017-8914-1_17] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Neuronal voltage-gated ion channels and ligand-gated synaptic receptors play a critical role in maintaining the delicate balance between neuronal excitation and inhibition within neuronal networks in the brain. Changes in expression of voltage-gated ion channels, in particular sodium, hyperpolarization-activated cyclic nucleotide-gated (HCN) and calcium channels, and ligand-gated synaptic receptors, in particular GABA and glutamate receptors, have been reported in many types of both genetic and acquired epilepsies, in animal models and in humans. In this chapter we review these and discuss the potential pathogenic role they may play in the epilepsies.
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Boehlen A, Schwake M, Dost R, Kunert A, Fidzinski P, Heinemann U, Gebhardt C. The new KCNQ2 activator 4-Chlor-N-(6-chlor-pyridin-3-yl)-benzamid displays anticonvulsant potential. Br J Pharmacol 2013; 168:1182-200. [PMID: 23176257 DOI: 10.1111/bph.12065] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Revised: 09/12/2012] [Accepted: 09/17/2012] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND AND PURPOSE KCNQ2-5 channels are voltage-gated potassium channels that regulate neuronal excitability and represent suitable targets for the treatment of hyperexcitability disorders. The effect of Chlor-N-(6-chlor-pyridin-3-yl)-benzamid was tested on KCNQ subtypes for its ability to alter neuronal excitability and for its anticonvulsant potential. EXPERIMENTAL APPROACH The effect of 4-Chlor-N-(6-chlor-pyridin-3-yl)-benzamid was evaluated using whole-cell voltage-clamp recordings from CHO cells and Xenopus laevis oocytes expressing different types of KCNQ channels. Epileptiform afterdischarges were recorded in fully amygdala-kindled rats in vivo. Neuronal excitability was assessed using field potential and whole cell recording in rat hippocampus in vitro. KEY RESULTS 4-Chlor-N-(6-chlor-pyridin-3-yl)-benzamid caused a hyperpolarizing shift of the activation curve and a pronounced slowing of deactivation in KCNQ2-mediated currents, whereas KCNQ3/5 heteromers remained unaffected. The effect was also apparent in the Retigabine-insensitive mutant KCNQ2-W236L. In fully amygdala-kindled rats, it elevated the threshold for induction of afterdischarges and reduced seizure severity and duration. In hippocampal CA1 cells, 4-Chlor-N-(6-chlor-pyridin-3-yl)-benzamid strongly damped neuronal excitability caused by a membrane hyperpolarization and a decrease in membrane resistance and induced an increase of the somatic resonance frequency on the single cell level, whereas synaptic transmission was unaffected. On the network level, 4-Chlor-N-(6-chlor-pyridin-3-yl)-benzamid caused a significant reduction of γ and θ oscillation peak power, with no significant change in oscillation frequency. CONCLUSION AND IMPLICATIONS Our data indicate that 4-Chlor-N-(6-chlor-pyridin-3-yl)-benzamid is a potent KCNQ activator with a selectivity for KCNQ2 containing channels. It strongly reduces neuronal excitability and displays anticonvulsant activity in vivo.
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Affiliation(s)
- A Boehlen
- Institute of Neurophysiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
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Lasoń W, Chlebicka M, Rejdak K. Research advances in basic mechanisms of seizures and antiepileptic drug action. Pharmacol Rep 2013; 65:787-801. [DOI: 10.1016/s1734-1140(13)71060-0] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 03/11/2013] [Indexed: 10/25/2022]
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Gavrilovici C, Pollock E, Everest M, Poulter MO. The loss of interneuron functional diversity in the piriform cortex after induction of experimental epilepsy. Neurobiol Dis 2012; 48:317-28. [PMID: 22801084 DOI: 10.1016/j.nbd.2012.07.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 06/28/2012] [Accepted: 07/05/2012] [Indexed: 11/20/2022] Open
Abstract
Interneuronal functional diversity is thought to be an important factor in the control of neural network oscillations in many brain regions. Specifically, interneuron action potential firing patterns are thought to modulate brain rhythms. In neurological disorders such as epilepsy where brain rhythms are significantly disturbed interneuron function is largely unexplored. Thus the purpose of this study was to examine the functional diversity of piriform cortex interneurons (PC; an area of the brain that easily supports seizures) before and after kindling-induced epilepsy. Using cluster analysis, we found five control firing behaviors. These groups were termed: non-adapting very high frequency (NAvHF), adapting high frequency (AHF), adapting low frequency (ALF), strongly adapting low frequency (sALF), and weakly adapting low frequency (wALF). A morphological analysis showed these spiking patterns were not associated with any specific interneuronal morphology although we found that most of the cells displaying NAvHF firing pattern were multipolar. After kindling about 40% of interneuronal firing pattern changed, and neither the NAvHF nor the wALF phenotypes were found. We also found that in multipolar interneurons a long-lasting potassium current was increased. A qPCR analysis indicated Kv1.6 subtype was up-regulated after kindling. An immunocytochemical analysis showed that Kv1.6 protein expression on parvalbumin (multipolar) interneurons increased by greater than 400%. We also examined whether these changes could be due to the selective death of a subset of interneurons but found that there was no change in cell number. These data show an important loss of the functional diversity of interneurons in the PC. Our data suggest that under pathophysiological condition interneurons are plastic resulting in the attenuation of high frequency network oscillations in favor of low frequency network activity. This may be an important new mechanism by which network synchrony is disturbed in epileptic seizures.
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Affiliation(s)
- Cezar Gavrilovici
- Molecular Brain Research Group, Robarts Research Institute, Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada N6A 5K8
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Su T, Cong W, Long Y, Luo A, Sun W, Deng W, Liao W. Altered expression of voltage-gated potassium channel 4.2 and voltage-gated potassium channel 4-interacting protein, and changes in intracellular calcium levels following lithium-pilocarpine-induced status epilepticus. Neuroscience 2008; 157:566-76. [DOI: 10.1016/j.neuroscience.2008.09.027] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2008] [Revised: 09/16/2008] [Accepted: 09/19/2008] [Indexed: 11/16/2022]
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Aroniadou-Anderjaska V, Fritsch B, Qashu F, Braga MFM. Pathology and pathophysiology of the amygdala in epileptogenesis and epilepsy. Epilepsy Res 2008; 78:102-16. [PMID: 18226499 PMCID: PMC2272535 DOI: 10.1016/j.eplepsyres.2007.11.011] [Citation(s) in RCA: 138] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2007] [Revised: 11/20/2007] [Accepted: 11/30/2007] [Indexed: 11/20/2022]
Abstract
Acute brain insults, such as traumatic brain injury, status epilepticus, or stroke are common etiologies for the development of epilepsy, including temporal lobe epilepsy (TLE), which is often refractory to drug therapy. The mechanisms by which a brain injury can lead to epilepsy are poorly understood. It is well recognized that excessive glutamatergic activity plays a major role in the initial pathological and pathophysiological damage. This initial damage is followed by a latent period, during which there is no seizure activity, yet a number of pathophysiological and structural alterations are taking place in key brain regions, that culminate in the expression of epilepsy. The process by which affected/injured neurons that have survived the acute insult, along with well-preserved neurons are progressively forming hyperexcitable, epileptic neuronal networks has been termed epileptogenesis. Understanding the mechanisms of epileptogenesis is crucial for the development of therapeutic interventions that will prevent the manifestation of epilepsy after a brain injury, or reduce its severity. The amygdala, a temporal lobe structure that is most well known for its central role in emotional behavior, also plays a key role in epileptogenesis and epilepsy. In this article, we review the current knowledge on the pathology of the amygdala associated with epileptogenesis and/or epilepsy in TLE patients, and in animal models of TLE. In addition, because a derangement in the balance between glutamatergic and GABAergic synaptic transmission is a salient feature of hyperexcitable, epileptic neuronal circuits, we also review the information available on the role of the glutamatergic and GABAergic systems in epileptogenesis and epilepsy in the amygdala.
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Affiliation(s)
- Vassiliki Aroniadou-Anderjaska
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
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