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Chong SA, Balosso S, Vandenplas C, Szczesny G, Hanon E, Claes K, Van Damme X, Danis B, Van Eyll J, Wolff C, Vezzani A, Kaminski RM, Niespodziany I. Intrinsic Inflammation Is a Potential Anti-Epileptogenic Target in the Organotypic Hippocampal Slice Model. Neurotherapeutics 2018; 15:470-488. [PMID: 29464573 PMCID: PMC5935638 DOI: 10.1007/s13311-018-0607-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Understanding the mechanisms of epileptogenesis is essential to develop novel drugs that could prevent or modify the disease. Neuroinflammation has been proposed as a promising target for therapeutic interventions to inhibit the epileptogenic process that evolves from traumatic brain injury. However, it remains unclear whether cytokine-related pathways, particularly TNFα signaling, have a critical role in the development of epilepsy. In this study, we investigated the role of innate inflammation in an in vitro model of post-traumatic epileptogenesis. We combined organotypic hippocampal slice cultures, representing an in vitro model of post-traumatic epilepsy, with multi-electrode array recordings to directly monitor the development of epileptiform activity and to examine the concomitant changes in cytokine release, cell death, and glial cell activation. We report that synchronized ictal- and interictal-like activities spontaneously evolve in this culture. Dynamic changes in the release of the pro-inflammatory cytokines IL-1β, TNFα, and IL-6 were observed throughout the culture period (3 to 21 days in vitro) with persistent activation of microglia and astrocytes. We found that neutralizing TNFα with a polyclonal antibody significantly reduced ictal discharges, and this effect lasted for 1 week after antibody washout. Neither phenytoin nor an anti-IL-6 polyclonal antibody was efficacious in inhibiting the development of epileptiform activity. Our data show a sustained effect of the anti-TNFα antibody on the ictal progression in organotypic hippocampal slice cultures supporting the critical role of inflammatory mediators in epilepsy and establishing a proof-of-principle evidence for the utility of this preparation to test the therapeutic effects of anti-inflammatory treatments.
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Affiliation(s)
- Seon-Ah Chong
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium.
| | - Silvia Balosso
- Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, 20156, Italy
| | | | - Gregory Szczesny
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Etienne Hanon
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Kasper Claes
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Xavier Van Damme
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Bénédicte Danis
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Jonathan Van Eyll
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Christian Wolff
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Annamaria Vezzani
- Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, 20156, Italy
| | - Rafal M Kaminski
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
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Chong SA, Balosso S, Vandenplas C, Szczesny G, Hanon E, Claes K, Van Damme X, Danis B, Van Eyll J, Wolff C, Vezzani A, Kaminski RM, Niespodziany I. Intrinsic Inflammation Is a Potential Anti-Epileptogenic Target in the Organotypic Hippocampal Slice Model. Neurotherapeutics 2018; 15:470-488. [PMID: 29464573 DOI: 10.1007/s13311-018-0607-6/figures/7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023] Open
Abstract
Understanding the mechanisms of epileptogenesis is essential to develop novel drugs that could prevent or modify the disease. Neuroinflammation has been proposed as a promising target for therapeutic interventions to inhibit the epileptogenic process that evolves from traumatic brain injury. However, it remains unclear whether cytokine-related pathways, particularly TNFα signaling, have a critical role in the development of epilepsy. In this study, we investigated the role of innate inflammation in an in vitro model of post-traumatic epileptogenesis. We combined organotypic hippocampal slice cultures, representing an in vitro model of post-traumatic epilepsy, with multi-electrode array recordings to directly monitor the development of epileptiform activity and to examine the concomitant changes in cytokine release, cell death, and glial cell activation. We report that synchronized ictal- and interictal-like activities spontaneously evolve in this culture. Dynamic changes in the release of the pro-inflammatory cytokines IL-1β, TNFα, and IL-6 were observed throughout the culture period (3 to 21 days in vitro) with persistent activation of microglia and astrocytes. We found that neutralizing TNFα with a polyclonal antibody significantly reduced ictal discharges, and this effect lasted for 1 week after antibody washout. Neither phenytoin nor an anti-IL-6 polyclonal antibody was efficacious in inhibiting the development of epileptiform activity. Our data show a sustained effect of the anti-TNFα antibody on the ictal progression in organotypic hippocampal slice cultures supporting the critical role of inflammatory mediators in epilepsy and establishing a proof-of-principle evidence for the utility of this preparation to test the therapeutic effects of anti-inflammatory treatments.
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Affiliation(s)
- Seon-Ah Chong
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium.
| | - Silvia Balosso
- Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, 20156, Italy
| | | | - Gregory Szczesny
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Etienne Hanon
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Kasper Claes
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Xavier Van Damme
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Bénédicte Danis
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Jonathan Van Eyll
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Christian Wolff
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
| | - Annamaria Vezzani
- Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, 20156, Italy
| | - Rafal M Kaminski
- UCB Biopharma SPRL, Chemin du Foriest, B-1420, Braine l'Alleud, Belgium
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Wang X, Wang Y, Zhang C, Liu C, Zhao B, Wei N, Zhang JG, Zhang K. CB1 receptor antagonism prevents long-term hyperexcitability after head injury by regulation of dynorphin-KOR system and mGluR5 in rat hippocampus. Brain Res 2016; 1646:174-181. [PMID: 27262683 DOI: 10.1016/j.brainres.2016.05.055] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 05/28/2016] [Accepted: 05/31/2016] [Indexed: 01/23/2023]
Abstract
Both endocannabinoids and dynorphin are feedback messengers in nervous system that act at the presynaptic nerve terminal to inhibit transmitter release. Many studies showed the cannabinoid-opioid cross-modulation in antinociception, hypothermia, sedation and reward. The aim of this study was to assess the influence of early application of cannabinoid type 1 (CB1) receptor antagonism SR141716A after brain injury on dynorphin-κ opioid receptor (KOR) system and the expression of metabotropic glutamate receptors (mGluRs) in a rat model of fluid percussion injury (FPI). Firstly, seizure latency induced by pentylenetetrazole was significantly prolonged 6 weeks after brain injury in group of SR141716A treatment. Then, PCR and western blot showed that SR141716A inhibited the long-term up-regulation of CB1 receptors in hippocampus. However, SR141716A resulted in long-term potentiation of dynorphin release and did not influence the up-regulation of KOR in hippocampus after brain injury. Furthermore, SR141716A reverse the overexpression of mGluR5 in the late stage of brain injury. We propose that during the induction of epileptogenesis after brain injury, early application of CB1 receptor antagonism could prevent long-term hyperexcitability by up-regulation of dynorphin-KOR system and prevention of mGluR5 induced epileptogenesis in hippocampus.
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Affiliation(s)
- Xiu Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Yao Wang
- Beijing Jingmei Group General Hospital, Heishan Street 18, Mentougou, Beijing 102300, China
| | - Chao Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Chang Liu
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Baotian Zhao
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Naili Wei
- Department of Neurosurgery, The Second Hospital of Lanzhou University, Chengguan District, Lanzhou, Gansu 730030, China
| | - Jian-Guo Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Neurosurgical Institute, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Kai Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Neurosurgical Institute, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China.
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Activation of extrasynaptic GABA(A) receptors inhibits cyclothiazide-induced epileptiform activity in hippocampal CA1 neurons. Neurosci Bull 2014; 30:866-76. [PMID: 25260800 DOI: 10.1007/s12264-014-1466-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 01/17/2014] [Indexed: 12/20/2022] Open
Abstract
Extrasynaptic GABA(A) receptors (GABA(A)Rs)-mediated tonic inhibition is reported to involve in the pathogenesis of epilepsy. In this study, we used cyclothiazide (CTZ)-induced in vitro brain slice seizure model to explore the effect of selective activation of extrasynaptic GABA(A)Rs by 4,5,6,7-tetrahydroisoxazolo[5,4-c] pyridine-3-ol (THIP) on the CTZ-induced epileptiform activity in hippocampal neurons. Perfusion with CTZ dose-dependently induced multiple epileptiform peaks of evoked population spikes (PSs) in CA1 pyramidal neurons, and treatment with THIP (5 μmol/L) significantly reduced the multiple PS peaks induced by CTZ stimulation. Western blot showed that the δ-subunit of the GABA(A)R, an extrasynaptic specific GABA(A)R subunit, was also significantly down-regulated in the cell membrane 2 h after CTZ treatment. Our results suggest that the CTZ-induced epileptiform activity in hippocampal CA1 neurons is suppressed by the activation of extrasynaptic GABA(A)Rs, and further support the hypothesis that tonic inhibition mediated by extrasynaptic GABA(A)Rs plays a prominent role in seizure generation.
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Ge J, Wang J, Xue D, Zhu Z, Chen Z, Li X, Su D, Du J. Why does a high-fat diet induce preeclampsia-like symptoms in pregnant rats. Neural Regen Res 2014; 8:1872-80. [PMID: 25206496 PMCID: PMC4145971 DOI: 10.3969/j.issn.1673-5374.2013.20.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 06/06/2013] [Indexed: 12/22/2022] Open
Abstract
Changes in neurotransmitter levels in the brain play an important role in epilepsy-like attacks after pregnancy-induced preeclampsia-eclampsia. Metabotropic glutamate receptor 1 participates in the onset of lipid metabolism disorder-induced preeclampsia. Pregnant rats were fed with a high-fat diet for 20 days. Thus, these pregnant rats experienced preeclampsia-like syndromes such as tension and proteinuria. Simultaneously, metabotropic glutamate receptor 1 mRNA and protein expressions were upregulated in the rat hippocampus. These findings indicate that increased sion of metabotropic glutamate receptor 1 promotes the occurrence of high-fat diet-induced preeclampsia in pregnant rats.
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Affiliation(s)
- Jing Ge
- Department of Gynecology and Obstetrics, Shengjing Hospital of China Medical University, Shenyang 110000, Liaoning Province, China ; The General Hospital of Shenyang Military Region, Shenyang 110016, Liaoning Province, China
| | - Jun Wang
- The General Hospital of Shenyang Military Region, Shenyang 110016, Liaoning Province, China
| | - Dan Xue
- Department of Gynecology and Obstetrics, People's Liberation Army No. 202 Hosiptal, Shenyang 110003, Liaoning Province, China
| | - Zhengsheng Zhu
- Dantu District Sanitary Supervision Institute, Zhenjiang 212001, Jiangsu Provicne, China
| | - Zhenyu Chen
- Department of Gynecology and Obstetrics, People's Liberation Army No. 202 Hosiptal, Shenyang 110003, Liaoning Province, China
| | - Xiaoqiu Li
- The General Hospital of Shenyang Military Region, Shenyang 110016, Liaoning Province, China
| | - Dongfeng Su
- Department of Neurology, the 463 Hospital of Chinese PLA, Shenyang 110042, Liaoning Province, China
| | - Juan Du
- Department of Gynecology and Obstetrics, Shengjing Hospital of China Medical University, Shenyang 110000, Liaoning Province, China
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Enhanced excitatory synaptic network activity following transient group I metabotropic glutamate activation. Neuroscience 2014; 275:22-32. [PMID: 24928353 DOI: 10.1016/j.neuroscience.2014.05.062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2014] [Revised: 05/02/2014] [Accepted: 05/31/2014] [Indexed: 02/02/2023]
Abstract
Prolonged activation of group I metabotropic glutamate receptors (mGluRs) using the agonist (S)-3,5-dihydroxyphenylglycine (DHPG) produces long-lasting changes in the CA3 region of the hippocampal slice. Changes in CA3 pyramidal neuron excitability that follow DHPG exposure result in abnormal network activity manifest by epileptiform activity that consists of interictal and longer lasting ictal epileptiform discharges. In this study we evaluated changes in synaptic activity of CA3 neurons in rat hippocampal slices that occurred after exposure to DHPG. Whole-cell voltage-clamp recordings were made from visually identified CA3 neurons in control artificial cerebrospinal fluid at times greater than 1h after DHPG exposure. Compared to control slices, neurons from slices exposed to DHPG showed enhanced amplitude and frequency of spontaneously occurring excitatory postsynaptic currents (EPSCs) without a concurrent change in inhibitory postsynaptic current (IPSC) amplitude or frequency. Miniature EPSCs were not affected by DHPG exposure but mIPSCs occurred less frequently and were of reduced amplitude. IPSCs recorded in the presence of ionotropic glutamate receptor blockade occurred less frequently in neurons that had been exposed to DHPG. Monosynaptic-evoked IPSPs were also reduced in amplitude in neurons that had been exposed to DHPG. Taken together, these findings demonstrated an enhanced network excitability of the CA3 region and failure of compensatory synaptic inhibition. We propose that prolonged activation of group I mGluR that may occur under conditions of pathological glutamate release results in long-lasting changes in CA3 synaptic network activity and epileptiform activity driven by excessive synaptic excitation.
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Ferraro TN. The relationship between genes affecting the development of epilepsy and approaches to epilepsy therapy. Expert Rev Neurother 2014; 14:329-52. [DOI: 10.1586/14737175.2014.888651] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Karr L, Pan YZ, Rutecki PA. CB1 receptor antagonism impairs the induction of epileptiform activity by group I metabotropic glutamate receptor activation. Epilepsia 2010; 51 Suppl 3:121-5. [PMID: 20618416 DOI: 10.1111/j.1528-1167.2010.02625.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Exposure to the group I metabotropic glutamate receptor (mGluR) agonist dihydroxy phenylglycine (DHPG) induces epileptiform activity in the CA3 region of the hippocampus that persists following washout of DHPG. DHPG also can cause long-term depression of synaptic transmission, and at some synapses this may be mediated by endocannabinoids. We evaluated whether the selective cannabinoid type 1 (CB1) receptor antagonists SR 141716 or AM 251 could modify induction of epileptiform activity produced by DHPG exposure. The induction of epileptiform activity by DHPG exposure was significantly reduced by CB1 receptor antagonists, SR 141716 or AM 251. Minimal effects on epileptiform activity were noted once the activity had been induced. In control slices, exposure to DHPG for 30 min produced long-term depression (LTD) of synaptic transmission, on average about a 70% reduction in slope of the field excitatory postsynaptic potential (EPSP). When slices were exposed to both DHPG and SR 141716 (3 microm), LTD did not occur and the population EPSP remained at control values or greater. These results suggest that CB1 receptors mediate some of DHPG effects that result in persistent epileptiform activity, and antagonism of CB1 receptors has antiepileptogenic properties. Paradoxically DHPG also caused LTD of excitatory synaptic transmission in the CA3 region and CB1 receptor antagonism prevents the depression. We hypothesize that the ictal activity induced by DHPG requires depression of synaptic strength and CB1 receptor antagonism prevents this depression and the induction of ictal activity.
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Affiliation(s)
- Linda Karr
- Neurology Service, William S Middleton Memorial Veterans Hospital, and Department of Neurology, University of Wisconsin, Madison, Wisconsin, USA
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Ictal activity induced by group I metabotropic glutamate receptor activation and loss of afterhyperpolarizations. Neuropharmacology 2010; 59:86-92. [PMID: 20385148 DOI: 10.1016/j.neuropharm.2010.04.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 03/03/2010] [Accepted: 04/05/2010] [Indexed: 11/20/2022]
Abstract
Exposure to the group I metabotropic glutamate receptor (mGluR) agonist dihydroxyphenylglycine (DHPG) produces long-lasting changes in network excitability and epileptiform activity in the CA3 region of rat hippocampal slices that continues in the absence of the agonist and includes both interictal and more prolonged ictal-like activity. We evaluated the afterhyperpolarization (AHP) that follows repetitive neuronal firing in neurons exposed to DHPG and related the change in the AHP to the pattern of epileptiform activity. In contrast to neurons from control slices that had a robust AHP following neuronal depolarization and action potential generation, neurons that had been exposed to DHPG displayed a minimal AHP following depolarization. Whole-cell voltage-clamp recordings showed a small outward or transient inward current following a depolarizing pulse in neurons from slices that had been exposed to DHPG while control neurons had a long-lasting outward current. In slices that demonstrated ictal patterns after exposure to DHPG, bath application of 1-ethyl-2-benzimidazolinone (1-EBIO, 1 mM) or 5,6-dichloro-1-ethyl-1,3-dihydro-2H-benzimidazol-2-one (DCEBIO, 100 microM) which enhance the AHP, suppressed ictal discharges. Whole-cell voltage-clamp recordings demonstrated the return of the medium and slow AHP current in neurons that had transiently been exposed to DHPG when 1-EBIO or DCEBIO was bath-applied. Co-application of either 1-EBIO or DCEBIO with DHPG blocked the induction of epileptiform activity. Transient DHPG exposure caused a long-term suppression of the AHP and ictal patterns of epileptiform activity. 1-EBIO or DCEBIO which re-established both the medium and slow AHP suppressed ictal discharges. These results support the hypothesis that the loss of the AHP contributes to the generation of ictal activity after transient DHPG exposure.
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Watanabe Y, Kaida Y, Takechi K, Kamei C. Anticonvulsant Effect of (RS)-1-Aminoindan-1,5-dicarboxylic Acid on Pentetrazol-Induced Kindled Seizures in Mice. Biol Pharm Bull 2010; 33:647-52. [DOI: 10.1248/bpb.33.647] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Yusuke Watanabe
- Department of Medicinal Pharmacology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
| | - Yuko Kaida
- Department of Medicinal Pharmacology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
| | - Kenshi Takechi
- Department of Medicinal Pharmacology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
| | - Chiaki Kamei
- Department of Medicinal Pharmacology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
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Szczurowska E, Mareš P. Controversial action of positive modulator of subtype 7 of metabotropic glutamate receptors AMN082 on cortical epileptic afterdischarges in immature rats. Eur J Pharmacol 2009; 623:37-40. [DOI: 10.1016/j.ejphar.2009.09.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2009] [Revised: 08/30/2009] [Accepted: 09/08/2009] [Indexed: 10/20/2022]
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