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Onisiforou A, Georgiou P, Zanos P. Role of group II metabotropic glutamate receptors in ketamine's antidepressant actions. Pharmacol Biochem Behav 2023; 223:173531. [PMID: 36841543 DOI: 10.1016/j.pbb.2023.173531] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 02/08/2023] [Accepted: 02/15/2023] [Indexed: 02/26/2023]
Abstract
Major Depressive Disorder (MDD) is a serious neuropsychiatric disorder afflicting around 16-17 % of the global population and is accompanied by recurrent episodes of low mood, hopelessness and suicidal thoughts. Current pharmacological interventions take several weeks to even months for an improvement in depressive symptoms to emerge, with a significant percentage of individuals not responding to these medications at all, thus highlighting the need for rapid and effective next-generation treatments for MDD. Pre-clinical studies in animals have demonstrated that antagonists of the metabotropic glutamate receptor subtype 2/3 (mGlu2/3 receptor) exert rapid antidepressant-like effects, comparable to the actions of ketamine. Therefore, it is possible that mGlu2 or mGlu3 receptors to have a regulatory role on the unique antidepressant properties of ketamine, or that convergent intracellular mechanisms exist between mGlu2/3 receptor signaling and ketamine's effects. Here, we provide a comprehensive and critical evaluation of the literature on these convergent processes underlying the antidepressant action of mGlu2/3 receptor inhibitors and ketamine. Importantly, combining sub-threshold doses of mGlu2/3 receptor inhibitors with sub-antidepressant ketamine doses induce synergistic antidepressant-relevant behavioral effects. We review the evidence supporting these combinatorial effects since sub-effective dosages of mGlu2/3 receptor antagonists and ketamine could reduce the risk for the emergence of significant adverse events compared with taking normal dosages. Overall, deconvolution of ketamine's pharmacological targets will give critical insights to influence the development of next-generation antidepressant treatments with rapid actions.
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Affiliation(s)
- Anna Onisiforou
- Department of Psychology, University of Cyprus, Nicosia 2109, Cyprus
| | - Polymnia Georgiou
- Department of Biological Sciences, University of Cyprus, Nicosia 2109, Cyprus; Department of Psychology, University of Wisconsin Milwaukee, WI 53211, USA
| | - Panos Zanos
- Department of Psychology, University of Cyprus, Nicosia 2109, Cyprus.
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2
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Luessen DJ, Conn PJ. Allosteric Modulators of Metabotropic Glutamate Receptors as Novel Therapeutics for Neuropsychiatric Disease. Pharmacol Rev 2022; 74:630-661. [PMID: 35710132 PMCID: PMC9553119 DOI: 10.1124/pharmrev.121.000540] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Metabotropic glutamate (mGlu) receptors, a family of G-protein-coupled receptors, have been identified as novel therapeutic targets based on extensive research supporting their diverse contributions to cell signaling and physiology throughout the nervous system and important roles in regulating complex behaviors, such as cognition, reward, and movement. Thus, targeting mGlu receptors may be a promising strategy for the treatment of several brain disorders. Ongoing advances in the discovery of subtype-selective allosteric modulators for mGlu receptors has provided an unprecedented opportunity for highly specific modulation of signaling by individual mGlu receptor subtypes in the brain by targeting sites distinct from orthosteric or endogenous ligand binding sites on mGlu receptors. These pharmacological agents provide the unparalleled opportunity to selectively regulate neuronal excitability, synaptic transmission, and subsequent behavioral output pertinent to many brain disorders. Here, we review preclinical and clinical evidence supporting the utility of mGlu receptor allosteric modulators as novel therapeutic approaches to treat neuropsychiatric diseases, such as schizophrenia, substance use disorders, and stress-related disorders.
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3
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Low-Frequency Stimulation Prevents Kindling-Induced Impairment through the Activation of the Endocannabinoid System. BIOMED RESEARCH INTERNATIONAL 2021; 2021:5526780. [PMID: 34222471 PMCID: PMC8225428 DOI: 10.1155/2021/5526780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 04/19/2021] [Accepted: 06/05/2021] [Indexed: 11/17/2022]
Abstract
Background Cannabinoid system affects memory and has anticonvulsant effects in epileptic models. In the current study, the role of cannabinoid 1 (CB1) receptors was investigated in amelioration of the effects of low-frequency stimulation (LFS) on learning and memory impairments in kindled rats. Methods Electrical stimulation of the hippocampal CA1 area was employed to kindle the animals. LFS was applied to the CA1 area in four trials following the last kindling stimulation. One group of animals received intraperitoneal injection of AM251 (0.1 μg/rat), a CB1 receptor antagonist, before the LFS application. Similarly, CB1 agonist WIN55-212-2 (WIN) was administrated to another group prior to LFS. The Morris water maze (MWM) and the novel object recognition (NOR) tests were executed 48 h after the last kindling stimulation to assess learning and memory. Results Applying LFS in the kindled+LFS group restored learning and memory impairments in the kindled rats. There was a significant difference between the kindled and the kindled+LFS groups in learning and memory. The application of AM251 reduced the LFS effects significantly. Adversely, WIN acted similarly to LFS and alleviated learning and memory deficits in the kindled+WIN group. In addition, WIN did not counteract the LFS enhancing effects in the KLFS+WIN group. Conclusions Improving effects of LFS on learning and memory impairments are mediated through the activation of the endocannabinoid (ECB) system.
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Xue M, Zhou SB, Liu RH, Chen QY, Zhuo M, Li XH. NMDA Receptor-Dependent Synaptic Depression in Potentiated Synapses of the Anterior Cingulate Cortex of adult Mice. Mol Pain 2021; 17:17448069211018045. [PMID: 34024172 PMCID: PMC8141994 DOI: 10.1177/17448069211018045] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Long-term potentiation (LTP) is an important molecular mechanism for chronic pain in the anterior cingulate cortex (ACC), a key cortical region for pain perception and emotional regulation. Inhibiting ACC LTP via various manipulations or pharmacological treatments blocks chronic pain. Long-term depression (LTD) is another form of synaptic plasticity in the ACC, which is also proved to be involved in the mechanisms of chronic pain. However, less is known about the interactive relationship between LTP and LTD in the ACC. Whether the synaptic depression could be induced after synaptic LTP in the ACC is not clear. In the present study, we used multi-channel field potential recording systems to study synaptic depression after LTP in the ACC of adult mice. We found that low frequency stimulus (LFS: 1 Hz, 15 min) inhibited theta burst stimulation (TBS)-induced LTP at 30 min after the induction of LTP. However, LFS failed to induce depression at 90 min after the induction of LTP. Furthermore, NMDA receptor antagonist AP-5 blocked the induction of synaptic depression after potentiation. The GluN2B-selective antagonist Ro25-6981 also inhibited the phenomenon in the ACC, while the GluN2A-selective antagonist NVP-AAM077 and the GluN2C/D-selective antagonist PPDA and UBP145 had no any significant effect. These results suggest that synaptic LTP can be depressed by LTD in a time dependent manner, and GluN2B-containing NMDA receptors play important roles in this form of synaptic depression.
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Affiliation(s)
- Man Xue
- Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Institute of Brain Research, Qingdao International Academician Park, Qingdao, China
| | - Si-Bo Zhou
- Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Institute of Brain Research, Qingdao International Academician Park, Qingdao, China
| | - Ren-Hao Liu
- Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Institute of Brain Research, Qingdao International Academician Park, Qingdao, China
| | - Qi-Yu Chen
- Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Institute of Brain Research, Qingdao International Academician Park, Qingdao, China
| | - Min Zhuo
- Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Institute of Brain Research, Qingdao International Academician Park, Qingdao, China.,Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Xu-Hui Li
- Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Institute of Brain Research, Qingdao International Academician Park, Qingdao, China.,Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
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5
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He XK, Liu HH, Chen SJ, Sun QQ, Yu G, Lei L, Niu ZY, Chen LD, Hsieh TH. Subsequent Acupuncture Reverses the Aftereffects of Intermittent Theta-Burst Stimulation. Front Neural Circuits 2021; 15:675365. [PMID: 33994957 PMCID: PMC8115810 DOI: 10.3389/fncir.2021.675365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 03/29/2021] [Indexed: 11/18/2022] Open
Abstract
Objective This study explored whether acupuncture affects the maintenance of long-term potentiation (LTP)-like plasticity induced by transcranial magnetic stimulation (TMS) and the acquisition of motor skills following repetitive sequential visual isometric pinch task (SVIPT) training. Methods Thirty-six participants were recruited. The changes in the aftereffects induced by intermittent theta-burst stimulation (iTBS) and followed acupuncture were tested by the amplitude motor evoked potential (MEP) at pre-and-post-iTBS for 30 min and at acupuncture-in and -off for 30 min. Secondly, the effects of acupuncture on SVIPT movement in inducing error rate and learning skill index were tested. Results Following one session of iTBS, the MEP amplitude was increased and maintained at a high level for 30 min. The facilitation of MEP was gradually decreased to the baseline level during acupuncture-in and did not return to a high level after needle extraction. The SVIPT-acupuncture group had a lower learning skill index than those in the SVIPT group, indicating that acupuncture intervention after SVIPT training may restrain the acquisition ability of one’s learning skills. Conclusion Acupuncture could reverse the LTP-like plasticity of the contralateral motor cortex induced by iTBS. Subsequent acupuncture may negatively affect the efficacy of the acquisition of learned skills in repetitive exercise training.
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Affiliation(s)
- Xiao-Kuo He
- Fifth Hospital of XiaMen, Xiamen, China.,Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Hui-Hua Liu
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | | | - Qian-Qian Sun
- Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Guo Yu
- Fifth Hospital of XiaMen, Xiamen, China
| | - Lei Lei
- Fifth Hospital of XiaMen, Xiamen, China
| | | | - Li-Dian Chen
- Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Tsung-Hsun Hsieh
- School of Physical Therapy, Graduate Institute of Rehabilitation Science, Chang Gung University, Taoyuan, Taiwan.,Neuroscience Research Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan.,Healthy Aging Research Center, Chang Gung University, Taoyuan, Taiwan
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6
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Khajei S, Mirnajafi-Zadeh J, Sheibani V, Ahmadi-Zeidabadi M, Masoumi-Ardakani Y, Rajizadeh MA, Esmaeilpour K. Electromagnetic field protects against cognitive and synaptic plasticity impairment induced by electrical kindling in rats. Brain Res Bull 2021; 171:75-83. [PMID: 33753209 DOI: 10.1016/j.brainresbull.2021.03.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 03/10/2021] [Accepted: 03/16/2021] [Indexed: 01/10/2023]
Abstract
Kindling results in abnormal synaptic potentiation and significant impairment in learning and memory. Electromagnetic field (EMF) effects on learning and memory in kindled animals and its effects on hippocampal neural activity are largely unknown. In the current study, the effects of EMF on learning and memory, as well as hippocampal synaptic plasticity, in kindled rats were investigated. EMF (10 mT; 100 Hz) was applied to fully kindled animals one hour/day for a period of one week. The behavioral and electrophysiological studies were performed 24 h following the EMF application. The kindled rats showed spatial learning deficits during the training phase of the Morris water maze (MWM) test. Moreover, there were increments in escape latency and path length compared to the sham group. The kindled rats spent less time in the target-quadrant probe test, indicating spatial memory impairment. Applying EMF to the KEMF group (kindling + EMF) restored learning and memory, and decreased escape latency and path length significantly compared to the kindled group. EMF alone had no significant effects on the learning and memory parameters. Based on the open field (OF) test results, EMF alone in the EMF group, but not in the kindled or the KEMF groups, decreased the total traveled distance and increased the spent time in the peripheral zone, compared to the sham group. Based on electrophysiological results, applying EMF in the KEMF group returned the ability of synaptic potentiation to the hippocampal CA1 area and high-frequency stimulation induced long-term potentiation (LTP). Accordingly, EMF can be considered a potential therapy for seizure-induced deficits in learning and memory.
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Affiliation(s)
- Sina Khajei
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Javad Mirnajafi-Zadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Vahid Sheibani
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Meysam Ahmadi-Zeidabadi
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Yaser Masoumi-Ardakani
- Physiology Research Center, Institute of Basic and Clinical Physiology Sciences, Kerman University of Medical Sciences, Kerman, Iran
| | - Mohammad Amin Rajizadeh
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Khadijeh Esmaeilpour
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran.
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Ferrari C, Vecchi T, Sciamanna G, Blandini F, Pisani A, Natoli S. Facemasks and face recognition: Potential impact on synaptic plasticity. Neurobiol Dis 2021; 153:105319. [PMID: 33647447 DOI: 10.1016/j.nbd.2021.105319] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 02/22/2021] [Accepted: 02/24/2021] [Indexed: 12/13/2022] Open
Abstract
Visual recognition of facial expression modulates our social interactions. Compelling experimental evidence indicates that face conveys plenty of information that are fundamental for humans to interact. These are encoded at neural level in specific cortical and subcortical brain regions through activity- and experience-dependent synaptic plasticity processes. The current pandemic, due to the spread of SARS-CoV-2 infection, is causing relevant social and psychological detrimental effects. The institutional recommendations on physical distancing, namely social distancing and wearing of facemasks are effective in reducing the rate of viral spread. However, by impacting social interaction, facemasks might impair the neural responses to recognition of facial cues that are overall critical to our behaviors. In this survey, we briefly review the current knowledge on the neurobiological substrate of facial recognition and discuss how the lack of salient stimuli might impact the ability to retain and consolidate learning and memory phenomena underlying face recognition. Such an "abnormal" visual experience raises the intriguing possibility of a "reset" mechanism, a renewed ability of adult brain to undergo synaptic plasticity adaptations.
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Affiliation(s)
- Chiara Ferrari
- Department of Brain and Behavioral Sciences, University of Pavia, Italy; IRCCS Mondino Foundation, Pavia, Italy
| | - Tomaso Vecchi
- Department of Brain and Behavioral Sciences, University of Pavia, Italy; IRCCS Mondino Foundation, Pavia, Italy
| | | | - Fabio Blandini
- Department of Brain and Behavioral Sciences, University of Pavia, Italy; IRCCS Mondino Foundation, Pavia, Italy
| | - Antonio Pisani
- Department of Brain and Behavioral Sciences, University of Pavia, Italy; IRCCS Mondino Foundation, Pavia, Italy.
| | - Silvia Natoli
- Department of Clinical Science and Translational Medicine, University of Rome Tor Vergata, Rome, Italy
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Fujii S, Yamazaki Y, Goto JI, Fujiwara H, Mikoshiba K. Depotentiation depends on IP 3 receptor activation sustained by synaptic inputs after LTP induction. ACTA ACUST UNITED AC 2020; 27:52-66. [PMID: 31949037 PMCID: PMC6970427 DOI: 10.1101/lm.050344.119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 10/29/2020] [Indexed: 12/14/2022]
Abstract
In CA1 neurons of guinea pig hippocampal slices, long-term potentiation (LTP) was induced in field excitatory postsynaptic potentials (EPSPs) or population spikes (PSs) by the delivery of high-frequency stimulation (HFS, 100 pulses at 100 Hz) to CA1 synapses, and was reversed by the delivery of a train of low-frequency stimulation (LFS, 1000 pulses at 2 Hz) at 30 min after HFS (depotentiation), and this effect was inhibited when test synaptic stimulation was halted for a 19-min period after HFS or for a 20-min period after LFS or applied over the same time period in the presence of an antagonist of N-methyl-D-aspartate receptors (NMDARs), group I metabotropic glutamate receptors (mGluRs), or inositol 1, 4, 5-trisphosphate receptors (IP3Rs). Depotentiation was also blocked by the application of a Ca2+/calmodulin-dependent protein kinase II (CaMKII) inhibitor or a calcineurin inhibitor applied in the presence of test synaptic input for a 10-min period after HFS or for a 20-min period after LFS. These results suggest that, in postsynaptic neurons, the coactivation of NMDARs and group I mGluRs due to sustained synaptic activity following LTP induction results in the activation of IP3Rs and CaMKII, which leads to the activation of calcineurin after LFS and depotentiation of CA1 synaptic responses.
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Affiliation(s)
- Satoshi Fujii
- Department of Physiology, Yamagata University School of Medicine, Yamagata 990-9585, Japan.,Laboratory for Developmental Neurobiology, Riken Brain Science Institute, Wako, Saitama 351-0198, Japan
| | - Yoshihiko Yamazaki
- Department of Physiology, Yamagata University School of Medicine, Yamagata 990-9585, Japan
| | - Jun-Ichi Goto
- Department of Physiology, Yamagata University School of Medicine, Yamagata 990-9585, Japan.,Laboratory for Developmental Neurobiology, Riken Brain Science Institute, Wako, Saitama 351-0198, Japan
| | - Hiroki Fujiwara
- Department of Physiology, Yamagata University School of Medicine, Yamagata 990-9585, Japan
| | - Katsuhiko Mikoshiba
- Laboratory for Developmental Neurobiology, Riken Brain Science Institute, Wako, Saitama 351-0198, Japan
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Griego E, Galván EJ. Metabotropic Glutamate Receptors at the Aged Mossy Fiber - CA3 Synapse of the Hippocampus. Neuroscience 2020; 456:95-105. [PMID: 31917351 DOI: 10.1016/j.neuroscience.2019.12.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 12/06/2019] [Accepted: 12/09/2019] [Indexed: 12/28/2022]
Abstract
Metabotropic glutamate receptors (mGluRs) are a group of G-protein-coupled receptors that exert a broad array of modulatory actions at excitatory synapses of the central nervous system. In the hippocampus, the selective activation of the different mGluRs modulates the intrinsic excitability, the strength of synaptic transmission, and induces multiple forms of long-term plasticity. Despite the relevance of mGluRs in the normal function of the hippocampus, we know very little about the changes that mGluRs functionality undergoes during the non-pathological aging. Here, we review data concerning the physiological actions of mGluRs, with particular emphasis on hippocampal area CA3. Later, we examine changes in the expression and functionality of mGluRs during the aging process. We complement this review with original data showing an array of electrophysiological modifications observed in the synaptic transmission and intrinsic excitability of aged CA3 pyramidal cells in response to the pharmacological stimulation of the different mGluRs.
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Affiliation(s)
- Ernesto Griego
- Departamento de Farmacobiología, Cinvestav Sede Sur, México City, Mexico
| | - Emilio J Galván
- Departamento de Farmacobiología, Cinvestav Sede Sur, México City, Mexico.
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10
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Gharib A, Komaki A, Manoochehri Khoshinani H, Saidijam M, Barkley V, Sarihi A, Mirnajafi-Zadeh J. Intrahippocampal 5-HT 1A receptor antagonist inhibits the improving effect of low-frequency stimulation on memory impairment in kindled rats. Brain Res Bull 2019; 148:109-117. [PMID: 30902574 DOI: 10.1016/j.brainresbull.2019.03.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 02/22/2019] [Accepted: 03/14/2019] [Indexed: 01/10/2023]
Abstract
In addition to its anticonvulsant effect, low frequency stimulation (LFS) improves learning and memory in kindled animals. In the present study, the role of 5-HT1A receptors in mediating LFS' improving effect on spatial learning and memory was investigated in amygdala-kindled rats. Amygdala kindling was conducted in a semi-rapid kindling stimulations (12 stimulations per day) in male Wistar rats. LFS (4 trains of 0.1 ms pulse duration at 1 Hz, 200 pulses, 50-150 μA, at 5 min intervals) was applied after termination of kindling stimulations. NAD-299 (a selective 5-HT1A receptor antagonist; 2.5 and 5 μg/μl) was microinjected into the hippocampal CA1 before applying LFS. The Morris water maze, and novel object recognition tests were conducted after the last kindling stimulation. Hippocampal samples were also prepared, and 5-HT1A receptor gene expression levels were assessed using quantitative RT-PCR. In kindled animals, LFS reduced impairments in spatial learning and memory in the Morris water maze and novel object recognition tests. Microinjection of NAD doses of 5 μg/μl reduced the effects of LFS on learning and memory. The gene expression level of 5-HT1A receptors increased significantly in the hippocampus of amygdala-kindled rats. However, LFS applied after kindling stimulations inhibited this effect. It seems that activation of 5-HT1A receptors in the CA1 field is necessary for LFS' improving effects on spatial learning and memory in kindled animals; although surprisingly, LFS application prevented the elevation in gene expression of 5-HT1A receptors in kindled animals.
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Affiliation(s)
- Alireza Gharib
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Alireza Komaki
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Hamed Manoochehri Khoshinani
- Department of Molecular Medicine and Genetics, School of Medicine, Hamedan University of Medical Sciences, Hamadan, Iran
| | - Massoud Saidijam
- Department of Molecular Medicine and Genetics, School of Medicine, Hamedan University of Medical Sciences, Hamadan, Iran
| | - Victoria Barkley
- Krembil Research Institute, University Health Network, Toronto, Canada
| | - Abdolrahman Sarihi
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
| | - Javad Mirnajafi-Zadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran; Institute for Brain Sciences and Cognition, Tarbiat Modares University, Tehran, Iran.
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( 2R,6R)-hydroxynorketamine exerts mGlu 2 receptor-dependent antidepressant actions. Proc Natl Acad Sci U S A 2019; 116:6441-6450. [PMID: 30867285 DOI: 10.1073/pnas.1819540116] [Citation(s) in RCA: 99] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Currently approved antidepressant drugs often take months to take full effect, and ∼30% of depressed patients remain treatment resistant. In contrast, ketamine, when administered as a single subanesthetic dose, exerts rapid and sustained antidepressant actions. Preclinical studies indicate that the ketamine metabolite (2R,6R)-hydroxynorketamine [(2R,6R)-HNK] is a rapid-acting antidepressant drug candidate with limited dissociation properties and abuse potential. We assessed the role of group II metabotropic glutamate receptor subtypes 2 (mGlu2) and 3 (mGlu3) in the antidepressant-relevant actions of (2R,6R)-HNK using behavioral, genetic, and pharmacological approaches as well as cortical quantitative EEG (qEEG) measurements in mice. Both ketamine and (2R,6R)-HNK prevented mGlu2/3 receptor agonist (LY379268)-induced body temperature increases in mice lacking the Grm3, but not Grm2, gene. This action was not replicated by NMDA receptor antagonists or a chemical variant of ketamine that limits metabolism to (2R,6R)-HNK. The antidepressant-relevant behavioral effects and 30- to 80-Hz qEEG oscillation (gamma-range) increases resultant from (2R,6R)-HNK administration were prevented by pretreatment with an mGlu2/3 receptor agonist and absent in mice lacking the Grm2, but not Grm3 -/-, gene. Combined subeffective doses of the mGlu2/3 receptor antagonist LY341495 and (2R,6R)-HNK exerted synergistic increases on gamma oscillations and antidepressant-relevant behavioral actions. These findings highlight that (2R,6R)-HNK exerts antidepressant-relevant actions via a mechanism converging with mGlu2 receptor signaling and suggest enhanced cortical gamma oscillations as a marker of target engagement relevant to antidepressant efficacy. Moreover, these results support the use of (2R,6R)-HNK and inhibitors of mGlu2 receptor function in clinical trials for treatment-resistant depression either alone or in combination.
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12
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Human Depotentiation following Induction of Spike Timing Dependent Plasticity. Biomedicines 2018; 6:biomedicines6020071. [PMID: 29912149 PMCID: PMC6027207 DOI: 10.3390/biomedicines6020071] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 05/17/2018] [Accepted: 06/04/2018] [Indexed: 11/16/2022] Open
Abstract
Depotentiation (DP) is a crucial mechanism for the tuning of memory traces once LTP (Long Term Potentiation) has been induced via learning, artificial procedures, or other activities. Putative unuseful LTP might be abolished via this process. Its deficiency is thought to play a role in pathologies, such as drug induced dyskinesia. However, since it is thought that it represents a mechanism that is linked to the susceptibility to interference during consolidation of a memory trace, it is an important process to consider when therapeutic interventions, such as psychotherapy, are administered. Perhaps a person with an abnormal depotentiation is prone to lose learned effects very easily or on the other end of the spectrum is prone to overload with previously generated unuseful LTP. Perhaps this process partly explains why some disorders and patients are extremely resistant to therapy. The present study seeks to quantify the relationship between LTP and depotentiation in the human brain by using transcranial magnetic stimulation (TMS) over the cortex of healthy participants. The results provide further evidence that depotentiation can be quantified in humans by use of noninvasive brain stimulation techniques. They provide evidence that a nonfocal rhythmic on its own inefficient stimulation, such as a modified thetaburst stimulation, can depotentiate an associative, focal spike timing-dependent PAS (paired associative stimulation)-induced LTP. Therefore, the depotentiation-like process does not seem to be restricted to specific subgroups of synapses that have undergone LTP before. Most importantly, the induced LTP seems highly correlated with the amount of generated depotentiation in healthy individuals. This might be a phenomenon typical of health and might be distorted in brain pathologies, such as dystonia, or dyskinesias. The ratio of LTP/DP might be a valuable marker for potential distortions of persistence versus deletion of memory traces represented by LTP-like plasticity.
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Abstract
Traditional pharmacological treatments for depression have a delayed therapeutic onset, ranging from several weeks to months, and there is a high percentage of individuals who never respond to treatment. In contrast, ketamine produces rapid-onset antidepressant, anti-suicidal, and anti-anhedonic actions following a single administration to patients with depression. Proposed mechanisms of the antidepressant action of ketamine include N-methyl-D-aspartate receptor (NMDAR) modulation, gamma aminobutyric acid (GABA)-ergic interneuron disinhibition, and direct actions of its hydroxynorketamine (HNK) metabolites. Downstream actions include activation of the mechanistic target of rapamycin (mTOR), deactivation of glycogen synthase kinase-3 and eukaryotic elongation factor 2 (eEF2), enhanced brain-derived neurotrophic factor (BDNF) signaling, and activation of α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptors (AMPARs). These putative mechanisms of ketamine action are not mutually exclusive and may complement each other to induce potentiation of excitatory synapses in affective-regulating brain circuits, which results in amelioration of depression symptoms. We review these proposed mechanisms of ketamine action in the context of how such mechanisms are informing the development of novel putative rapid-acting antidepressant drugs. Such drugs that have undergone pre-clinical, and in some cases clinical, testing include the muscarinic acetylcholine receptor antagonist scopolamine, GluN2B-NMDAR antagonists (i.e., CP-101,606, MK-0657), (2R,6R)-HNK, NMDAR glycine site modulators (i.e., 4-chlorokynurenine, pro-drug of the glycineB NMDAR antagonist 7-chlorokynurenic acid), NMDAR agonists [i.e., GLYX-13 (rapastinel)], metabotropic glutamate receptor 2/3 (mGluR2/3) antagonists, GABAA receptor modulators, and drugs acting on various serotonin receptor subtypes. These ongoing studies suggest that the future acute treatment of depression will typically occur within hours, rather than months, of treatment initiation.
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Affiliation(s)
- Panos Zanos
- Department of Psychiatry, University of Maryland School of Medicine, Rm. 934F MSTF, 685 W. Baltimore St., Baltimore, MD, 21201, USA.
| | - Scott M Thompson
- Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Physiology, University of Maryland School of Medicine, St. BRB 5-007, 655 W. Baltimore St., Baltimore, MD, 21201, USA, Baltimore, MD, 21201, USA
| | - Ronald S Duman
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Department of Neurobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Carlos A Zarate
- Experimental Therapeutics and Pathophysiology Branch, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Todd D Gould
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Psychiatry, University of Maryland School of Medicine, Rm. 936 MSTF, 685 W. Baltimore St., Baltimore, MD, 21201, USA
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Huang YZ, Lu MK, Antal A, Classen J, Nitsche M, Ziemann U, Ridding M, Hamada M, Ugawa Y, Jaberzadeh S, Suppa A, Paulus W, Rothwell J. Plasticity induced by non-invasive transcranial brain stimulation: A position paper. Clin Neurophysiol 2017; 128:2318-2329. [DOI: 10.1016/j.clinph.2017.09.007] [Citation(s) in RCA: 198] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 08/31/2017] [Accepted: 09/05/2017] [Indexed: 12/11/2022]
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15
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Esmaeilpour K, Sheibani V, Shabani M, Mirnajafi-Zadeh J. Low frequency electrical stimulation has time dependent improving effect on kindling-induced impairment in long-term potentiation in rats. Brain Res 2017; 1668:20-27. [DOI: 10.1016/j.brainres.2017.05.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Revised: 04/28/2017] [Accepted: 05/08/2017] [Indexed: 10/19/2022]
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16
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Low Frequency Electrical Stimulation Either Prior to Or after Rapid Kindling Stimulation Inhibits the Kindling-Induced Epileptogenesis. BIOMED RESEARCH INTERNATIONAL 2017; 2017:8623743. [PMID: 28373988 PMCID: PMC5360964 DOI: 10.1155/2017/8623743] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Revised: 01/21/2017] [Accepted: 01/31/2017] [Indexed: 12/18/2022]
Abstract
Objective. Studies are ongoing to find appropriate low frequency stimulation (LFS) protocol for treatment of epilepsy. The present study aimed at assessing the antiepileptogenesis effects of LFS with the same protocol applied either just before or immediately after kindling stimulations. Method. This experimental animal study was conducted on adult Wistar rats (200 ± 20 g) randomly divided into kindle (n = 7), LFS + Kindle (n = 6), and Kindle + LFS groups (n = 6). All animals underwent rapid kindling procedure and four packages of LFS (1 Hz) with 5 min interval were applied either immediately before (LFS-K) or after kindling stimulation (K-LFS). The after discharge duration (ADD), daily stages of kindling, and kindling seizure stage and number of stimulations required to reach each stage were compared between the three groups using two-way analysis of variance (ANOVA) followed by Tukey post hoc and one-way ANOVA, and Kruskal-Wallis test, respectively. Results. LFS in both protocols significantly decreased the ADD (p < 0.05) and daily seizure stages (p < 0.05) and increased the number of stimulations required to achieve stage 3 and stages 4 and 5 of kindling compared with the kindle group (stage 2: p > 0.05, stages 3 to 5: p < 0.05). Conclusion. Although LFS-K showed more inhibiting effect than K-LFS, the difference was not statistically significant.
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The antiepileptogenic effect of low-frequency stimulation on perforant path kindling involves changes in regulators of G-protein signaling in rat. J Neurol Sci 2017; 375:450-459. [PMID: 28320185 DOI: 10.1016/j.jns.2017.02.047] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 01/27/2017] [Accepted: 02/20/2017] [Indexed: 02/02/2023]
Abstract
G-protein coupled receptors may have a role in mediating the antiepileptogenic effect of low-frequency stimulation (LFS) on kindling acquisition. This effect is accompanied by changes at the intracellular level of cAMP. In the present study, the effect of rolipram as a phosphodiesterase inhibitor on the antiepileptogenic effect of LFS was investigated. Meanwhile, the expression of αs- and αi-subunit of G proteins and regulators of G-protein signaling (RGS) proteins following LFS application was measured. Male Wistar rats were kindled by perforant path stimulation in a semi-rapid kindling manner (12 stimulations per day) during a period of 6days. Application of LFS (0.1ms pulse duration at 1Hz, 200 pulses, 50-150μA, 5min after termination of daily kindling stimulations) to the perforant path retarded the kindling development and prevented the kindling-induced potentiation and kindling-induced changes in paired pulse indices in the dentate gyrus. Intra-cerebroventricular microinjection of rolipram (0.25μM) partially prevented these LFS effects. Twenty-four hours after the last kindling stimulation, the dentate gyrus was removed and changes in protein expression were measured by Western blotting. There was no significant difference in the expression of α-subunit of Gs and Gi/o proteins in different experimental groups. However, application of LFS during the kindling procedure decreased the expression RGS4 and RGS10 proteins (that reduce the activity of Gi/o) and prevented the kindling-induced decrease of RGS2 protein (which reduces the Gs activity). Therefore, it can be postulated that the Gi/o protein signaling pathways may be involved in antiepileptogenetic effect of LFS, and this is why decreasing the cAMP metabolism by rolipram attenuates this effect of LFS.
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Esmaeilpour K, Sheibani V, Shabani M, Mirnajafi-Zadeh J. Effect of low frequency electrical stimulation on seizure-induced short- and long-term impairments in learning and memory in rats. Physiol Behav 2016; 168:112-121. [PMID: 27825910 DOI: 10.1016/j.physbeh.2016.11.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 10/31/2016] [Accepted: 11/03/2016] [Indexed: 12/21/2022]
Abstract
Kindled seizures can impair learning and memory. In the present study the effect of low-frequency electrical stimulation (LFS) on kindled seizure-induced impairment in spatial learning and memory was investigated and followed up to one month. Animals were kindled by electrical stimulation of hippocampal CA1 area in a semi-rapid manner (12 stimulations per day). One group of animals received four trials of LFS at 30s, 6h, 24h, and 30h following the last kindling stimulation. Each LFS trial was consisted of 4 packages at 5min intervals. Each package contained 200 monophasic square wave pulses of 0.1ms duration at 1Hz. The Open field, Morris water maze, and novel object recognition tests were done 48h, 1week, 2weeks, and one month after the last kindling stimulation respectively. Kindled animals showed a significant impairment in learning and memory compared to control rats. LFS decreased the kindling-induced learning and memory impairments at 24h and one week following its application, but not at 2week or 1month after kindling. In the group of animals that received the same 4 trials of LFS again one week following the last kindling stimulation, the improving effect of LFS was observed even after one month. Obtained results showed that application of LFS in fully kindled animals has a long-term improving effect on spatial learning and memory. This effect can remain for a long duration (one month in this study) by increasing the number of applied LFS.
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Affiliation(s)
- Khadijeh Esmaeilpour
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Vahid Sheibani
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Mohammad Shabani
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Javad Mirnajafi-Zadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
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Liu Y, Du S, Lv L, Lei B, Shi W, Tang Y, Wang L, Zhong Y. Hippocampal Activation of Rac1 Regulates the Forgetting of Object Recognition Memory. Curr Biol 2016; 26:2351-7. [DOI: 10.1016/j.cub.2016.06.056] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 06/22/2016] [Accepted: 06/24/2016] [Indexed: 01/02/2023]
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20
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Role of postsynaptic inositol 1, 4, 5-trisphosphate receptors in depotentiation in guinea pig hippocampal CA1 neurons. Brain Res 2016; 1642:154-162. [DOI: 10.1016/j.brainres.2016.03.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 03/12/2016] [Accepted: 03/22/2016] [Indexed: 11/19/2022]
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21
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Almaguer-Melian W, Mercerón-Martínez D, Delgado-Ocaña S, Pavón-Fuentes N, Ledón N, Bergado JA. EPO induces changes in synaptic transmission and plasticity in the dentate gyrus of rats. Synapse 2016; 70:240-52. [PMID: 26860222 DOI: 10.1002/syn.21895] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 02/04/2016] [Accepted: 02/05/2016] [Indexed: 12/24/2022]
Abstract
Erythropoietin has shown wide physiological effects on the central nervous system in animal models of disease, and in healthy animals. We have recently shown that systemic EPO administration 15 min, but not 5 h, after daily training in a water maze is able to induce the recovery of spatial memory in fimbria-fornix chronic-lesioned animals, suggesting that acute EPO triggers mechanisms which can modulate the active neural plasticity mechanism involved in spatial memory acquisition in lesioned animals. Additionally, this EPO effect is accompanied by the up-regulation of plasticity-related early genes. More remarkably, this time-dependent effects on learning recovery could signify that EPO in nerve system modulate specific living-cellular processes. In the present article, we focus on the question if EPO could modulate the induction of long-term synaptic plasticity like LTP and LTD, which presumably could support our previous published data. Our results show that acute EPO peripheral administration 15 min before the induction of synaptic plasticity is able to increase the magnitude of the LTP (more prominent in PSA than fEPSP-Slope) to facilitate the induction of LTD, and to protect LTP from depotentiation. These findings showing that EPO modulates in vivo synaptic plasticity sustain the assumption that EPO can act not only as a neuroprotective substance, but is also able to modulate transient neural plasticity mechanisms and therefore to promote the recovery of nerve function after an established chronic brain lesion. According to these results, EPO could be use as a molecular tool for neurorestaurative treatments.
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Affiliation(s)
| | | | | | - Nancy Pavón-Fuentes
- Centro Internacional De Restauración Neurológica (CIREN), La Habana 11300, Cuba
| | - Nuris Ledón
- Centro De Inmunología Molecular, Playa, 11600, La Habana, Cuba
| | - Jorge A Bergado
- Centro Internacional De Restauración Neurológica (CIREN), La Habana 11300, Cuba
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Status Epilepticus Enhances Depotentiation after Fully Established LTP in an NMDAR-Dependent but GluN2B-Independent Manner. Neural Plast 2016; 2016:6592038. [PMID: 26881126 PMCID: PMC4735914 DOI: 10.1155/2016/6592038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 10/26/2015] [Accepted: 11/01/2015] [Indexed: 11/22/2022] Open
Abstract
N-Methyl-D-aspartate (NMDA) receptor-dependent long-term potentiation (LTP) can be reversed by low-frequency stimulation (LFS) referred to as depotentiation (DP). We previously found GluN2B upregulated in CA1 neurons from post-status epilepticus (post-SE) tissue associated with an enhanced LTP. Here, we tested whether LFS-induced DP is also altered in pathological GluN2B upregulation. Although LTP was enhanced in post-SE tissue, LTP was significantly reversed in this tissue, but not in controls. We next tested the effect of the GluN2B subunit-specific blocker Ro 25-6981 (1 μM) on LFS-DP. As expected, LFS had no effect on synaptic strength in the presence of the GluN2B blocker in control tissue. In marked contrast, LFS-DP was also attained in post-SE tissue indicating that GluN2B was obviously not involved in depotentiation. To test for NMDA receptor-dependence, we applied the NMDA receptor antagonist D-AP5 (50 μM) prior to LFS and observed that DP was abolished in both control and post-SE tissue confirming NMDA receptor involvement. These results indicate that control Schaffer collateral-CA1 synapses cannot be depotentiated after fully established LTP, but LFS was able to reverse LTP significantly in post-SE tissue. However, while LFS-DP clearly required NMDA receptor activation, GluN2B-containing NMDA receptors were not involved in this form of depotentiation.
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23
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Kadowaki S, Enomoto H, Murakami T, Nakatani-Enomoto S, Kobayashi S, Ugawa Y. Influence of phasic muscle contraction upon the quadripulse stimulation (QPS) aftereffects. Clin Neurophysiol 2015; 127:1568-1573. [PMID: 26702773 DOI: 10.1016/j.clinph.2015.10.063] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 10/06/2015] [Accepted: 10/23/2015] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Contractions of the target muscle influence the aftereffects of repetitive transcranial magnetic stimulation (rTMS). The aim of this paper is to investigate whether or not voluntary hand movement influences the aftereffects of quadripulse stimulation (QPS) on the hand motor area. METHODS Thirteen healthy volunteers participated in this study. After QPS-5 or QPS-50 intervention over the motor hot spot for the right first dorsal interosseous muscle (FDI), the subjects performed voluntary motor tasks (opening-closing right hand movements at 1 Hz for 1 min). We compared the time courses of MEP size between the conditions with and without voluntary movement. RESULTS When the subjects moved their hands immediately after QPS, both QPS-5 and QPS-50 aftereffects were abolished. However, if they moved their hands at 20 min after QPS, the long-term aftereffects were preserved. CONCLUSIONS Voluntary hand movement applied after intervention influences QPS aftereffects, but the magnitude of the influence depends on the delay between QPS and the voluntary movement. SIGNIFICANCE In the plasticity induction experiments, we should always be mindful of the fact that voluntary movement, including the target muscle, seriously influences the induced long-term effects of QPS.
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Affiliation(s)
- Suguru Kadowaki
- Department of Neurology, School of Medicine, Fukushima Medical University, Fukushima, Japan.
| | - Hiroyuki Enomoto
- Department of Neurology, School of Medicine, Fukushima Medical University, Fukushima, Japan
| | - Takenobu Murakami
- Department of Neurology, School of Medicine, Fukushima Medical University, Fukushima, Japan
| | - Setsu Nakatani-Enomoto
- Department of Neurology, School of Medicine, Fukushima Medical University, Fukushima, Japan
| | - Shunsuke Kobayashi
- Department of Neurology, School of Medicine, Fukushima Medical University, Fukushima, Japan
| | - Yoshikazu Ugawa
- Department of Neurology, School of Medicine, Fukushima Medical University, Fukushima, Japan
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24
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Goldsworthy MR, Pitcher JB, Ridding MC. Spaced Noninvasive Brain Stimulation. Neurorehabil Neural Repair 2014; 29:714-21. [DOI: 10.1177/1545968314562649] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Neuroplasticity is critical for learning, memory, and recovery of lost function following neurological damage. Noninvasive brain stimulation (NIBS) techniques can induce neuroplastic changes in the human cortex that are behaviorally relevant, raising the exciting possibility that these techniques might be therapeutically beneficial for neurorehabilitation following brain injury. However, the short duration and instability of induced effects currently limits their usefulness. To date, trials investigating the therapeutic value of neuroplasticity-inducing NIBS have used either single or multiple treatment sessions, typically repeated once-daily for 1 to 2 weeks. Although multiple stimulation sessions are presumed to have cumulative effects on neuroplasticity induction, there is little direct scientific evidence to support this “once-daily” approach. In animal models, the repeated application of stimulation protocols spaced using relatively short intervals (typically of the order of minutes) induces long-lasting and stable changes in synaptic efficacy. Likewise, learning through spaced repetition facilitates the establishment of long-term memory. In both cases, the spacing interval is critical in determining the outcome. Emerging evidence in healthy human populations suggests that the within-session spacing of NIBS protocols may be an effective approach for significantly prolonging the duration of induced neuroplastic changes. Similar to findings in the animal and learning literature, the interval at which spaced NIBS is applied seems to be a critical factor influencing the neuroplastic response. In this Point of View article, we propose that to truly exploit the therapeutic opportunities provided by NIBS, future clinical trials should consider the optimal spacing interval for repeated applications.
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Affiliation(s)
- Mitchell R. Goldsworthy
- Robinson Research Institute, School of Paediatrics and Reproductive Health, University of Adelaide, Adelaide, SA, Australia
| | - Julia B. Pitcher
- Robinson Research Institute, School of Paediatrics and Reproductive Health, University of Adelaide, Adelaide, SA, Australia
| | - Michael C. Ridding
- Robinson Research Institute, School of Paediatrics and Reproductive Health, University of Adelaide, Adelaide, SA, Australia
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25
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Chida K, Kaneko K, Fujii S, Yamazaki Y. Activity-dependent modulation of the axonal conduction of action potentials along rat hippocampal mossy fibers. Eur J Neurosci 2014; 41:45-54. [PMID: 25345805 DOI: 10.1111/ejn.12762] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 09/08/2014] [Accepted: 09/25/2014] [Indexed: 01/20/2023]
Abstract
The axonal conduction of action potentials in the nervous system is generally considered to be a stable signal for the relaying of information, and its dysfunction is involved in impairment of cognitive function. Recent evidence suggests that the conduction properties and excitability of axons are more variable than traditionally thought. To investigate possible changes in the conduction of action potentials along axons in the central nervous system, we recorded action potentials from granule cells that were evoked and conducted antidromically along unmyelinated mossy fibers in the rat hippocampus. To evaluate changes in axons by eliminating any involvement of changes in the somata, two latency values were obtained by stimulating at two different positions and the latency difference between the action potentials was measured. A conditioning electrical stimulus of 20 pulses at 1 Hz increased the latency difference and this effect, which lasted for approximately 30 s, was inhibited by the application of an α-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA)/kainate receptor antagonist or a GluK1-containing kainate receptor antagonist, but not by an AMPA receptor-selective antagonist or an N-methyl-d-aspartate receptor antagonist. These results indicated that axonal conduction in mossy fibers is modulated in an activity-dependent manner through the activation of GluK1-containing kainate receptors. These dynamic changes in axonal conduction may contribute to the physiology and pathophysiology of the brain.
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Affiliation(s)
- Kuniaki Chida
- Department of Physiology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata, 990-9585, Japan
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26
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Goldsworthy MR, Müller-Dahlhaus F, Ridding MC, Ziemann U. Resistant Against De-depression: LTD-Like Plasticity in the Human Motor Cortex Induced by Spaced cTBS. Cereb Cortex 2014; 25:1724-34. [DOI: 10.1093/cercor/bht353] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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27
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Suppressive effect of preconditioning low-frequency stimulation on subsequent induction of long-term potentiation by high frequency stimulation in hippocampal CA3 neurons. Brain Res 2012; 1449:15-23. [PMID: 22405691 DOI: 10.1016/j.brainres.2012.02.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 02/07/2012] [Accepted: 02/10/2012] [Indexed: 11/24/2022]
Abstract
We investigated the role of inositol 1, 4, 5-trisphosphate receptors (IP3Rs), activated during preconditioning low-frequency afferent stimulation (LFS), in the subsequent induction of long-term potentiation (LTP) in CA3 neurons in hippocampal slices from mature guinea pigs. Induction of LTP in the field excitatory postsynaptic potential (EPSP) by the delivery of high-frequency stimulation (HFS, a tetanus of two trains of 100 pulses at 100Hz with a 10s interval) to mossy fiber-CA3 neuron synapses was suppressed when CA3 synapses were preconditioned by the LFS of 1000 pulses at 2Hz and this effect was inhibited when the LFS preconditioning was performed in the presence of an IP3R antagonist or a protein phosphatase inhibitor. Furthermore, activation of group 1 metabotropic glutamate receptors (mGluRs) during HFS canceled the effects of an IP3R antagonist given during preconditioning LFS on the subsequent LTP induction at mossy fiber-CA3 synapses. These results suggest that, in hippocampal mossy fiber-CA3 neuron synapses, activation of IP3Rs during a preconditioning LFS results in dephosphorylation events that lead to failure of the HFS to induce subsequent LTP.
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28
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Cosgrove KE, Galván EJ, Barrionuevo G, Meriney SD. mGluRs modulate strength and timing of excitatory transmission in hippocampal area CA3. Mol Neurobiol 2011; 44:93-101. [PMID: 21559753 DOI: 10.1007/s12035-011-8187-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Accepted: 04/28/2011] [Indexed: 01/25/2023]
Abstract
Excitatory transmission within hippocampal area CA3 stems from three major glutamatergic pathways: the perforant path formed by axons of layer II stellate cells in the entorhinal cortex, the mossy fiber axons originating from the dentate gyrus granule cells, and the recurrent axon collaterals of CA3 pyramidal cells. The synaptic communication of each of these pathways is modulated by metabotropic glutamate receptors that fine-tune the signal by affecting both the timing and strength of the connection. Within area CA3 of the hippocampus, group I mGluRs (mGluR1 and mGluR5) are expressed postsynaptically, whereas group II (mGluR2 and mGluR3) and III mGluRs (mGluR4, mGluR7, and mGluR8) are expressed presynaptically. Receptors from each group have been demonstrated to be required for different forms of pre- and postsynaptic long-term plasticity and also have been implicated in regulating short-term plasticity. A recent observation has demonstrated that a presynaptically expressed mGluR can affect the timing of action potentials elicited in the postsynaptic target. Interestingly, mGluRs can be distributed in a target-specific manner, such that synaptic input from one presynaptic neuron can be modulated by different receptors at each of its postsynaptic targets. Consequently, mGluRs provide a mechanism for synaptic specialization of glutamatergic transmission in the hippocampus. This review will highlight the variability in mGluR modulation of excitatory transmission within area CA3 with an emphasis on how these receptors contribute to the strength and timing of network activity within pyramidal cells and interneurons.
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Affiliation(s)
- Kathleen E Cosgrove
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
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29
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Yamazaki Y, Sugihara T, Goto JI, Chida K, Fujiwara H, Kaneko K, Fujii S, Mikoshiba K. Role of inositol 1, 4, 5-trisphosphate receptors in the postsynaptic expression of guinea pig hippocampal mossy fiber depotentiation. Brain Res 2011; 1387:19-28. [DOI: 10.1016/j.brainres.2011.02.088] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Revised: 02/24/2011] [Accepted: 02/26/2011] [Indexed: 11/26/2022]
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30
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Huang YZ, Rothwell JC, Lu CS, Chuang WL, Lin WY, Chen RS. Reversal of plasticity-like effects in the human motor cortex. J Physiol 2010; 588:3683-93. [PMID: 20660564 DOI: 10.1113/jphysiol.2010.191361] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
A number of experiments in animals have shown that successful induction of plasticity can be abolished if an individually ineffective intervention is given shortly afterwards. Such effects are termed depotentiation/de-depression. These effects contrast with metaplasticity/homeostatic plasticity in which pretreatment of the system with one protocol modulates the response to a second plasticity-inducing protocol. Homeostatic plasticity maintains the balance of plasticity in the nervous system at a stable level whereas depotentiation/de-depression abolishes synaptic plasticity that has just occurred in order to prevent ongoing learning. In the present study, we developed novel protocols to explore the reversal of LTP- and LTD-like effects in healthy conscious humans based on the recently developed theta burst form of repetitive transcranial magnetic stimulation (TBS). The potentiation effect induced by intermittent TBS (iTBS) was completely erased by a short form of continuous TBS (cTBS150) given 1 min after iTBS, whereas the depressive effect of continuous TBS (cTBS) was successfully abolished by a short form of iTBS (iTBS150). The reversal was specific to the nature of the second protocol and was time dependent since it was less effective when the intervention was given 10 min after induction of plasticity. All these features are compatible with those of depotentiation and de-depression demonstrated in animal studies. The development of the present protocols would be helpful to study the physiology of the reversal of plasticity and learning and to probe the abnormal depotentiation/de-depression shown in animal models of neurological diseases (e.g. Parkinson's disease with dyskinesia, dystonia and Huntingon's disease).
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Affiliation(s)
- Ying-Zu Huang
- Department of Neurology, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taipei 10507, Taiwan
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Chen CC, Yang CH, Huang CC, Hsu KS. Acute stress impairs hippocampal mossy fiber-CA3 long-term potentiation by enhancing cAMP-specific phosphodiesterase 4 activity. Neuropsychopharmacology 2010; 35:1605-17. [PMID: 20237461 PMCID: PMC3055459 DOI: 10.1038/npp.2010.33] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The mossy fiber synapses onto hippocampal CA3 neurons show unique molecular features and a wide dynamic range of plasticity. Although acute stress has been well recognized to alter bidirectional long-term synaptic plasticity in the hippocampal CA1 region and dentate gyrus, it remains unclear whether the same effect may also occur at the mossy fiber-CA3 synapses. Here, we report that hippocampal slices prepared from adult mice that had experienced an acute unpredictable and inescapable restraint tail-shock stress showed a marked impairment of long-term potentiation (LTP) induced by high-frequency stimulation or adenylyl cyclase activator forskolin. This effect was prevented when animals were submitted to bilateral adrenalectomy or given the glucocorticoid receptor antagonist RU38486 before experiencing stress. In contrast, stress has no effect on synaptic potentiation induced by the non-hydrolysable and membrane-permeable cyclic adenosine 5'-monophosphate (cAMP) analog Sp-8-bromo-cAMPS. No obvious differences were observed between control and stressed mice in the basal synaptic transmission, paired-pulse facilitation, or frequency facilitation at the mossy fiber-CA3 synapses. We also found that the inhibitory effect of stress on mossy fiber LTP was obviated by the adenosine A(1) receptor antagonist 8-cyclopentyl-1,3,-dipropylxanthine, the non-specific phosphodiesterase (PDE) inhibitor 3-isobutyl-methylxanthine, and the specific PDE4 inhibitor 4-(3-butoxy-4-methoxyphenyl)methyl-2-imidazolidone. In addition, stress induces a sustained and profound increase in cAMP-specific PDE4 activity. These results suggest that the inhibition of mossy fiber LTP by acute stress treatment seems originating from a corticosterone-induced sustained increase in the PDE4 activity to accelerate the metabolism of cAMP to adenosine, in turn triggering an adenosine A(1) receptor-mediated impairment of transmitter release machinery.
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Affiliation(s)
- Chien-Chung Chen
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chih-Hao Yang
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chiung-Chun Huang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Kuei-Sen Hsu
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan,Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan,Center for Gene Regulation and Signal Transduction Research, National Cheng Kung University, Tainan, Taiwan,Department of Pharmacology, College of Medicine, National Cheng Kung University, No. 1, University Road, Tainan City 701, Taiwan, Tel: +886 6235 3535 ext: 5498, Fax: +886 6274 9296, E-mail:
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Sun HL, Zhang SH, Zhong K, Xu ZH, Zhu W, Fang Q, Wu DC, Hu WW, Xiao B, Chen Z. Mode-dependent effect of low-frequency stimulation targeting the hippocampal CA3 subfield on amygdala-kindled seizures in rats. Epilepsy Res 2010; 90:83-90. [DOI: 10.1016/j.eplepsyres.2010.03.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2010] [Revised: 03/16/2010] [Accepted: 03/17/2010] [Indexed: 12/01/2022]
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Kobayashi K. Hippocampal Mossy Fiber Synaptic Transmission and Its Modulation. VITAMINS AND HORMONES 2010; 82:65-85. [DOI: 10.1016/s0083-6729(10)82004-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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Hagena H, Manahan-Vaughan D. Frequency facilitation at mossy fiber-CA3 synapses of freely behaving rats contributes to the induction of persistent LTD via an adenosine-A1 receptor-regulated mechanism. Cereb Cortex 2009; 20:1121-30. [PMID: 19903765 PMCID: PMC2852506 DOI: 10.1093/cercor/bhp184] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Frequency facilitation (FF), comprising a rapid and multiple-fold increase in the magnitude of evoked field potentials, is elicited by low-frequency stimulation (LFS) at mossy fiber-CA3 synapses. Here, we show that in freely behaving rats, FF reliably occurs in response to 1 and 2Hz but not in response to 0.25-, 0.3-, or 0.5-Hz LFS. Strikingly, prolonged (approximately 600 s) FF was tightly correlated to the induction of long-term depression (LTD) in freely moving animals. Although LFS at 2 Hz elicited unstable FF and unstable LTD, application of LFS at 1 Hz elicited pronounced FF, as well as robust LTD that persisted for over 24 h. This correlation of prolonged FF with LTD was absent at stimulation frequencies that did not induce FF. The adenosine-A1 receptor appears to participate in these effects: Application of adenosine-A1, but not adenosine-A3, receptor antagonists enhanced mossy fiber synaptic transmission and occluded FF. Furthermore, adenosine-A1 receptor antagonism resulted in more stable FF at 1 or 2 Hz and elicited more potent LTD. These data support the fact that FF contributes to the enablement of long-term information storage at mossy fiber-CA3 synapses and that the adenosine-A1 receptor may regulate the thresholds for this process.
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Affiliation(s)
- Hardy Hagena
- Department of Experimental Neurophysiology, Medical Faculty, Ruhr University Bochum, 44780 Bochum, Germany
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35
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Martella G, Tassone A, Sciamanna G, Platania P, Cuomo D, Viscomi MT, Bonsi P, Cacci E, Biagioni S, Usiello A, Bernardi G, Sharma N, Standaert DG, Pisani A. Impairment of bidirectional synaptic plasticity in the striatum of a mouse model of DYT1 dystonia: role of endogenous acetylcholine. ACTA ACUST UNITED AC 2009; 132:2336-49. [PMID: 19641103 DOI: 10.1093/brain/awp194] [Citation(s) in RCA: 172] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
DYT1 dystonia is a severe form of inherited dystonia, characterized by involuntary twisting movements and abnormal postures. It is linked to a deletion in the dyt1 gene, resulting in a mutated form of the protein torsinA. The penetrance for dystonia is incomplete, but both clinically affected and non-manifesting carriers of the DYT1 mutation exhibit impaired motor learning and evidence of altered motor plasticity. Here, we characterized striatal glutamatergic synaptic plasticity in transgenic mice expressing either the normal human torsinA or its mutant form, in comparison to non-transgenic (NT) control mice. Medium spiny neurons recorded from both NT and normal human torsinA mice exhibited normal long-term depression (LTD), whereas in mutant human torsinA littermates LTD could not be elicited. In addition, although long-term potentiation (LTP) could be induced in all the mice, it was greater in magnitude in mutant human torsinA mice. Low-frequency stimulation (LFS) can revert potentiated synapses to resting levels, a phenomenon termed synaptic depotentiation. LFS induced synaptic depotentiation (SD) both in NT and normal human torsinA mice, but not in mutant human torsinA mice. Since anti-cholinergic drugs are an effective medical therapeutic option for the treatment of human dystonia, we reasoned that an excess in endogenous acetylcholine could underlie the synaptic plasticity impairment. Indeed, both LTD and SD were rescued in mutant human torsinA mice either by lowering endogenous acetylcholine levels or by antagonizing muscarinic M1 receptors. The presence of an enhanced acetylcholine tone was confirmed by the observation that acetylcholinesterase activity was significantly increased in the striatum of mutant human torsinA mice, as compared with both normal human torsinA and NT littermates. Moreover, we found similar alterations of synaptic plasticity in muscarinic M2/M4 receptor knockout mice, in which an increased striatal acetylcholine level has been documented. The loss of LTD and SD on one hand, and the increase in LTP on the other, demonstrate that a 'loss of inhibition' characterizes the impairment of synaptic plasticity in this model of DYT1 dystonia. More importantly, our results indicate that an unbalanced cholinergic transmission plays a pivotal role in these alterations, providing a clue to understand the ability of anticholinergic agents to restore motor deficits in dystonia.
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Zhang L, Meng K, Li YH, Han TZ. NR2A-containing NMDA receptors are required for L-LTP induction and depotentiation in CA1 region of hippocampal slices. Eur J Neurosci 2009; 29:2137-44. [PMID: 19490087 DOI: 10.1111/j.1460-9568.2009.06783.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Long-term potentiation (LTP) is a well-characterized form of synaptic plasticity that fulfills many of the criteria for the neural correlate of memory. LTP reversal (or depotentiation, DP) is thought to correlate with prevention or elimination of memory storage. LTP during and immediately after induction can be easily reversed by afferent stimulation, when applied within the optimal time window. The aim of the present study was to determine whether later-phase LTP (L-LTP) could be reversed by special patterned stimulation applied at 2 h after LTP induction, as well as to characterize the receptor mechanisms underlying this reversal. Field excitatory postsynaptic potentials evoked by Schaffer collateral stimulation were recorded from the CA1 subfield of adult rat hippocampal slices. Results demonstrated that stable LTP, which was induced by six theta-burst stimulations, was mediated by NR2A-containing N-methyl-d-aspartate receptors (NMDARs). This L-LTP was partially reversed by high-intensity paired-pulse low-frequency stimulation (HI-PP-LFS) and was inhibited by Zn(2+) (30 nm), a voltage-independent NR2A-NMDAR antagonist. However, NR2B-NMDAR antagonists (Ro 25-6981, 1 mum) displayed no effect on L-LTP reversal. L-LTP partial reversal was also induced by HI-PP-LFS, when the protein synthesis inhibitors anisomycin (25 microm) and cycloheximide (60 microm) were applied following LTP induction. These results suggested that NR2A-containing NMDARs are required for L-LTP induction and DP in the hippocampal CA1 area of adult rats. Moreover, HI-PP-LFS was an effective stimulation pattern to induce DP.
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Affiliation(s)
- Li Zhang
- Department of Physiology, School of Medicine, Xi'an Jiaotong University, Zhuque Dajie 205, Xi'an 710061, China
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Zhang SH, Sun HL, Fang Q, Zhong K, Wu DC, Wang S, Chen Z. Low-frequency stimulation of the hippocampal CA3 subfield is anti-epileptogenic and anti-ictogenic in rat amygdaloid kindling model of epilepsy. Neurosci Lett 2009; 455:51-5. [PMID: 19429105 DOI: 10.1016/j.neulet.2009.03.041] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 03/05/2009] [Accepted: 03/11/2009] [Indexed: 11/25/2022]
Abstract
Neuromodulation with low-frequency stimulation (LFS), of brain structures other than epileptic foci, is effective in inhibiting seizures in animals and patients, whereas selection of targets for LFS requires further investigation. The hippocampal CA(3) subfield is a key site in the circuit of seizure generation and propagation. The present study aimed to illustrate the effects of LFS of the CA(3) region on seizure acquisition and generalization in the rat amygdaloid kindling model of epilepsy. We found that LFS (monophasic square-wave pulses, 1Hz, 100 microA and 0.1ms per pulse) of the CA(3) region significantly depressed the duration of epileptiform activity and seizure acquisition by retarding progression from focal to generalized seizures (GS). Moreover, GS duration was significantly shortened and its latency was significantly increased in the LFS group demonstrating an inhibition of the severity of GS and the spread of epileptiform activity. Furthermore, LFS prevented the decline of afterdischarge threshold (ADT) and elevated GS threshold indicating an inhibition of susceptibility to GS. These results suggest that LFS of the hippocampal CA(3) subfield is anti-epileptogenic and anti-ictogenic. Neuromodulation of CA(3) activity using LFS may be an alternative potential approach for temporal lobe epilepsy treatment.
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Affiliation(s)
- Shi-Hong Zhang
- Institute of Neuroscience, School of Medicine, Zhejiang University, Hangzhou 310058, China
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38
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Sağlam M, Matsunaga K, Murayama N, Hayashida Y, Huang YZ, Nakanishi R. Parallel inhibition of cortico-muscular synchronization and cortico-spinal excitability by theta burst TMS in humans. Clin Neurophysiol 2008; 119:2829-38. [DOI: 10.1016/j.clinph.2008.09.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2008] [Revised: 08/21/2008] [Accepted: 09/08/2008] [Indexed: 10/21/2022]
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39
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Mohammad-Zadeh M, Mirnajafi-Zadeh J, Fathollahi Y, Javan M, Jahanshahi A, Noorbakhsh SM, Motamedi F. The role of adenosine A(1) receptors in mediating the inhibitory effects of low frequency stimulation of perforant path on kindling acquisition in rats. Neuroscience 2008; 158:1632-43. [PMID: 19041928 DOI: 10.1016/j.neuroscience.2008.11.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2008] [Revised: 11/03/2008] [Accepted: 11/04/2008] [Indexed: 10/21/2022]
Abstract
Low frequency stimulation (LFS) has an inhibitory effect on rapid perforant path kindling acquisition. In the present study the role of adenosine A(1) and A(2A) receptors in mediating this inhibitory effect was investigated. Rats were kindled by perforant path stimulation using rapid kindling procedures (12 stimulations per day). LFS (0.1 ms pulse duration at 1 Hz, 200 pulses, and 50-150 muA) was applied to the perforant path immediately after termination of each rapid kindling stimulation. 1,3-Dimethyl-8-cyclopenthylxanthine (CPT; 50 muM), a selective A(1) antagonist and ZM241385 (ZM, 200 muM), a selective A(2A) antagonist were daily microinjected into the lateral ventricle 5 min before kindling stimulations. LFS had an inhibitory effect on kindling development. Pretreatment of animals with CPT reduced the inhibitory effect of LFS on kindling rate and suppressed the effects of LFS on potentiation of population EPSP during kindling acquisition. In addition, CPT was able to antagonize the effects of LFS on kindling-induced increase in early (10-50 ms intervals) and late (300-1000 ms intervals) paired pulse depression. ZM pretreatment had no effect on antiepileptogenic effects of LFS in kindling acquisition. In addition, LFS prevented the kindling-induced elevation of cyclic AMP (cAMP) levels in kindled animals. Based on these results, we suggest that the antiepileptogenic effects of LFS on perforant path kindling might be mediated through activation of adenosine A(1), but not A(2A) receptors. Moreover, modulation of cAMP levels by LFS may potentially be an important mechanism which explains the anticonvulsant effects of LFS in kindled seizures.
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Affiliation(s)
- M Mohammad-Zadeh
- Department of Physiology, School of Medical Sciences, Tarbiat Modares University, Tehran, IR Iran
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40
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Pinheiro PS, Mulle C. Presynaptic glutamate receptors: physiological functions and mechanisms of action. Nat Rev Neurosci 2008; 9:423-36. [PMID: 18464791 DOI: 10.1038/nrn2379] [Citation(s) in RCA: 251] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Glutamate acts on postsynaptic glutamate receptors to mediate excitatory communication between neurons. The discovery that additional presynaptic glutamate receptors can modulate neurotransmitter release has added complexity to the way we view glutamatergic synaptic transmission. Here we review evidence of a physiological role for presynaptic glutamate receptors in neurotransmitter release. We compare the physiological roles of ionotropic and metabotropic glutamate receptors in short- and long-term regulation of synaptic transmission. Furthermore, we discuss the physiological conditions that are necessary for their activation, the source of the glutamate that activates them, their mechanisms of action and their involvement in higher brain function.
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Affiliation(s)
- Paulo S Pinheiro
- Laboratoire Physiologie Cellulaire de la Synapse, Centre National de la Recherche Scientifique Unite mixte de recherche 5091, Bordeaux Neuroscience Institute, University of Bordeaux, 33077 Bordeaux, France
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41
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Imre G. The preclinical properties of a novel group II metabotropic glutamate receptor agonist LY379268. CNS DRUG REVIEWS 2008; 13:444-64. [PMID: 18078428 DOI: 10.1111/j.1527-3458.2007.00024.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Activation of group II metabotropic glutamate (mGlu2/3) receptors reduces excessive glutamate release that is often associated with neurodegenerative and psychiatric disorders. This finding encouraged the search for potent and selective agonists as potential therapeutic agents. The search led to the discovery of LY379268 {(-)-2-oxa-4-aminobicyclo[3.1.0]hexane-4,6-dicarboxylic acid}, which is a highly potent and systemically available mGlu2/3 receptor agonist. LY379268 was effective in several animal models of stroke, epilepsy, drug abuse, schizophrenia, and pain. Suppression of motor activity is the major side effect of LY379268. Upon repeated administration tolerance develops to this side effect, while the therapeutic effects of LY379268 remain. To date, no clinical data with LY379268 are available. This review article summarizes the preclinical pharmacology of LY379268.
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Affiliation(s)
- Gabor Imre
- Department of Behavioral Pharmacology, Gedeon Richter Ltd., Budapest, Hungary.
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Picconi B, Paillé V, Ghiglieri V, Bagetta V, Barone I, Lindgren HS, Bernardi G, Angela Cenci M, Calabresi P. l-DOPA dosage is critically involved in dyskinesia via loss of synaptic depotentiation. Neurobiol Dis 2008; 29:327-35. [DOI: 10.1016/j.nbd.2007.10.001] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2007] [Revised: 09/27/2007] [Accepted: 10/01/2007] [Indexed: 10/22/2022] Open
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Huang YZ, Rothwell JC, Edwards MJ, Chen RS. Effect of physiological activity on an NMDA-dependent form of cortical plasticity in human. Cereb Cortex 2007; 18:563-70. [PMID: 17573373 DOI: 10.1093/cercor/bhm087] [Citation(s) in RCA: 249] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Retention of motor learning can be enhanced or degraded by subsequent performance of a different task. Neurophysiologically this may reflect interference in synaptic plasticity by ongoing neural activity in the brain. Here we demonstrate that N-methyl-D-aspartate (NMDA) dependent aftereffects of repetitive transcranial magnetic stimulation (rTMS) also are subject to interference effects, suggesting that it may be possible to investigate these basic mechanisms in the intact human brain. We measured the motor-evoked potential (MEP) amplitude and short-interval intracortical inhibition (SICI) in the first dorsal interosseous (FDI) muscle after continuous or intermittent theta burst (cTBS/iTBS) forms of rTMS. In resting subjects, cTBS depressed MEPs and reduced SICI for about 20 min, whereas iTBS had the opposite effect. However, if subjects contracted the FDI during TBS, then effects on the MEP were abolished, although effects of cTBS on SICI remained. Contraction immediately after TBS enhanced the facilitatory effect of iTBS and reversed the usual inhibitory effect of cTBS into facilitation. Contraction 10 min after cTBS (iTBS not tested) had only a transient (3-4 min) effect on MEPs. These interactions with behavior may relate to mechanisms of interference between learning paradigms in human and be similar to effects on synaptic long-term potentiation/depression described in animal experiments.
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Affiliation(s)
- Ying-Zu Huang
- Department of Neurology, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taipei 10507, Taiwan.
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44
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Lin YW, Yang HW, Wang HJ, Gong CL, Chiu TH, Min MY. Spike-timing-dependent plasticity at resting and conditioned lateral perforant path synapses on granule cells in the dentate gyrus: different roles of N-methyl-D-aspartate and group I metabotropic glutamate receptors. Eur J Neurosci 2006; 23:2362-74. [PMID: 16706844 DOI: 10.1111/j.1460-9568.2006.04730.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We examined the mechanisms underlying spike-timing-dependent plasticity induction at resting and conditioned lateral perforant pathway (LPP) synapses in the rat dentate gyrus. Two stimulating electrodes were placed in the outer third of the molecular layer and in the granule cell layer in hippocampal slices to evoke field excitatory postsynaptic potentials (fEPSPs) and antidromic field somatic spikes (afSSs), respectively. Long-term potentiation (LTP) of LPP synapses was induced by paired stimulation with fEPSP preceding afSS. Reversal of the temporal order of fEPSP and afSS stimulation resulted in long-term depression (LTD). Induction of LTP or LTD was blocked by D,L-2-amino-5-phosphonopentanoic acid (AP5), showing that both effects were N-methyl-D-aspartate receptor (NMDAR)-dependent. Induction of LTP was also blocked by inhibitors of calcium-calmodulin kinase II, protein kinase C or mitogen-activated/extracellular-signal regulated kinase, suggesting that these are downstream effectors of NMDAR activation, whereas induction of LTD was blocked by inhibitors of protein kinase C and protein phosphatase 2B. At LPP synapses previously potentiated by high-frequency stimulation or depressed by low-frequency stimulation, paired fEPSP-afSS stimulation resulted in 'de-depression' at depressed LPP synapses but had no effect on potentiated synapses, whereas reversal of the temporal order of fEPSP-afSS stimulation resulted in 'de-potentiation' at potentiated synapses but had no effect on depressed synapses. Induction of de-depression and de-potentiation was unaffected by ap5 but was blocked by 2-methyl-6-(phenylethynyl) pyridine hydrochloride, a group I metabotropic glutamate receptor blocker, showing that both were NMDAR-independent but group I metabotropic glutamate receptor-dependent. In conclusion, our results show that spike-timing-dependent plasticity can occur at both resting and conditioned LPP synapses, its induction in the former case being NMDAR-dependent and, in the latter, group I metabotropic glutamate receptor-dependent.
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Affiliation(s)
- Yi-Wen Lin
- Department of Life Science, College of Life Science, National Taiwan University, 1 Sec.4 Roosevelt Road, Taipei 106, Taiwan
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Origlia N, Kuczewski N, Aztiria E, Gautam D, Wess J, Domenici L. Muscarinic acetylcholine receptor knockout mice show distinct synaptic plasticity impairments in the visual cortex. J Physiol 2006; 577:829-40. [PMID: 17023506 PMCID: PMC1890385 DOI: 10.1113/jphysiol.2006.117119] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
In the present report, we focused our attention on the role played by the muscarinic acetylcholine receptors (mAChRs) in different forms of long-term synaptic plasticity. Specifically, we investigated long-term potentiation (LTP) and long-term depression (LTD) expression elicited by theta-burst stimulation (TBS) and low-frequency stimulation (LFS), respectively, in visual cortical slices obtained from different mAChR knockout (KO) mice. A normal LTP was evoked in M(1)/M(3) double KO mice, while LTP was impaired in the M(2)/M(4) double KO animals. On the other hand, LFS induced LTD in M(2)/M(4) double KO mice, but failed to do so in M(1)/M(3) KO mice. Interestingly, LFS produced LTP instead of LTD in M(1)/M(3) KO mice. Analysis of mAChR single KO mice revealed that LTP was affected only by the simultaneous absence of both M(2) and M(4) receptors. A LFS-dependent shift from LTD to LTP was also observed in slices from M(1) KO mice, while LTD was simply abolished in slices from M(3) KO mice. Using pharmacological tools, we showed that LTP in control mice was blocked by pertussis toxin, an inhibitor of G(i/o) proteins, but not by raising intracellular cAMP levels. In addition, the inhibition of phospholipase C by U73122 induced the same shift from LTD to LTP after LFS observed in M(1) single KO and M(1)/M(3) double KO mice. Our results indicate that different mAChR subtypes regulate different forms of long-term synaptic plasticity in the mouse visual cortex, activating specific G proteins and downstream intracellular mechanisms.
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Rossi P, Mapelli L, Roggeri L, Gall D, de Kerchove d'Exaerde A, Schiffmann SN, Taglietti V, D'Angelo E. Inhibition of constitutive inward rectifier currents in cerebellar granule cells by pharmacological and synaptic activation of GABABreceptors. Eur J Neurosci 2006; 24:419-32. [PMID: 16903850 DOI: 10.1111/j.1460-9568.2006.04914.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
gamma-Aminobutyric acid (GABA)(B) receptors are known to enhance activation of Kir3 channels generating G-protein-dependent inward rectifier K(+)-currents (GIRK). In some neurons, GABA(B) receptors either cause a tonic GIRK activation or generate a late K(+)-dependent inhibitory postsynaptic current component. However, other neurons express Kir2 channels, which generate a constitutive inward rectifier K(+)-current (CIRK) without requiring G-protein activation. The functional coupling of CIRK with GABA(B) receptors remained unexplored so far. About 50% of rat cerebellar granule cells in the internal granular layer of P19-26 rats showed a sizeable CIRK current. Here, we have investigated CIRK current regulation by GABA(B) receptors in cerebellar granule cells, which undergo GABAergic inhibition through Golgi cells. By using patch-clamp recording techniques and single-cell reverse transcriptase-polymerase chain reaction in acute cerebellar slices, we show that granule cells co-express Kir2 channels and GABA(B) receptors. CIRK current biophysical properties were compatible with Kir2 but not Kir3 channels, and could be inhibited by the GABA(B) receptor agonist baclofen. The action of baclofen was prevented by the GABA(B) receptor blocker CGP35348, involved a pertussis toxin-insensitive G-protein-mediated pathway, and required protein phosphatases inhibited by okadaic acid. GABA(B) receptor-dependent CIRK current inhibition could also be induced by repetitive GABAergic transmission at frequencies higher than the basal autorhythmic discharge of Golgi cells. These results suggest therefore that GABA(B) receptors can exert an inhibitory control over CIRK currents mediated by Kir2 channels. CIRK inhibition was associated with an increased input resistance around rest and caused a approximately 5 mV membrane depolarization. The pro-excitatory action of these effects at an inhibitory synapse may have an homeostatic role re-establishing granule cell readiness under conditions of strong inhibition.
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Affiliation(s)
- Paola Rossi
- Department of Cellular-Molecular Physiological and Pharmacological Sciences, University of Pavia, Via Forlanini 6, I-27100, Pavia, Italy.
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Nicholls RE, Zhang XL, Bailey CP, Conklin BR, Kandel ER, Stanton PK. mGluR2 acts through inhibitory Galpha subunits to regulate transmission and long-term plasticity at hippocampal mossy fiber-CA3 synapses. Proc Natl Acad Sci U S A 2006; 103:6380-5. [PMID: 16606834 PMCID: PMC1458886 DOI: 10.1073/pnas.0601267103] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Presynaptic inhibitory G protein-coupled receptors play a critical role in regulating transmission at a number of synapses in the central and peripheral nervous system. We generated transgenic mice that express a constitutively active form of an inhibitory Galpha subunit to examine the molecular mechanisms underlying the actions of one such receptor, metabotropic glutamate receptor (mGluR) 2, at mossy fiber-CA3 synapses in the hippocampus. mGluR2 participates in at least three types of mossy fiber synaptic plasticity, (i) transient suppression of synaptic transmission, (ii) long-term depression (LTD), and (iii) inhibition of long-term potentiation (LTP), and we find that inhibitory Galpha signaling is sufficient to account for the actions of mGluR2 in each. The fact that constitutively active Galphai2 occludes the transient suppression of synaptic transmission by mGluR2, while enhancing LTD, suggests further that these two forms of plasticity are expressed via different mechanisms. In addition, the LTP deficit observed in constitutively active Galphai2-expressing mice suggests that mGluR2 activation may serve as a metaplastic switch to permit the induction of LTD by inhibiting LTP.
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Affiliation(s)
| | | | - Christopher P. Bailey
- Department of Pharmacology, University of Bristol, Bristol BS8 1TD, United Kingdom; and
| | - Bruce R. Conklin
- The J. David Gladstone Institute of Cardiovascular Disease, Departments of Medicine and Pharmacology, University of California, San Francisco, CA 94158
| | - Eric R. Kandel
- *Center for Neurobiology and Behavior
- Howard Hughes Medical Institute, and
- **Kavli Institute for Brain Sciences, Columbia University, New York, NY 10032
- To whom correspondence should be addressed. E-mail:
| | - Patric K. Stanton
- Departments of Cell Biology and Anatomy and
- Neurology, New York Medical College, Valhalla, NY 10595
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48
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Huang CC, Hsu KS. Local protein synthesis and GABAB receptors regulate the reversibility of long-term potentiation at murine hippocampal mossy fibre-CA3 synapses. J Physiol 2004; 561:91-108. [PMID: 15345751 PMCID: PMC1665341 DOI: 10.1113/jphysiol.2004.072546] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Reversal of long-term potentiation (LTP) by long trains of low-frequency stimulation is generally referred to as depotentiation. One of the intriguing aspects of depotentiation is that the magnitude of depotentiation is inversely proportional to the time lag of depotentiation stimulation following LTP induction. Although the mechanisms underlying depotentiation have been widely explored, the factors that regulate the susceptibility of LTP to depotentiation stimulation remain largely unclear. We now report that multiple trains of high-frequency stimulation provide immediate synaptic resistance to depotentiation stimulation at the mossy fibre-CA3 synapses. The synaptic resistance to depotentiation stimulation depends on the amount of synaptic stimulation used to induce LTP; it is prevented by protein synthesis inhibitors and is input specific. In contrast, neither the transection of mossy fibre axons near granule cell somata nor the application of RNA synthesis inhibitors influences synaptic resistance to depotentiation stimulation. We also provide evidence that the induction of depotentiation is regulated by GABA(B) receptors. Application of a GABA(B) receptor antagonist significantly promoted the synaptic resistance to depotentiation stimulation, whereas inhibition of GABA transport delayed the onset of this synaptic resistance. These results suggest that local protein synthesis is required for the development of synaptic resistance to depotentiation stimulation, whereas the activation of GABA(B) receptors promotes the susceptibility to depotentiation stimulation. These two factors may crucially regulate the reversal and stability of long-term information storage.
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Affiliation(s)
- Chiung-Chun Huang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, No. 1, Ta-Hsiue Road, Tainan 701, Taiwan
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Wang J, Yeckel MF, Johnston D, Zucker RS. Photolysis of postsynaptic caged Ca2+ can potentiate and depress mossy fiber synaptic responses in rat hippocampal CA3 pyramidal neurons. J Neurophysiol 2003; 91:1596-607. [PMID: 14645386 PMCID: PMC2867667 DOI: 10.1152/jn.01073.2003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The induction of mossy fiber-CA3 long-term potentiation (LTP) and depression (LTD) has been variously described as being dependent on either pre- or postsynaptic factors. Some of the postsynaptic factors for LTP induction include ephrin-B receptor tyrosine kinases and a rise in postsynaptic Ca2+ ([Ca2+]i). Ca2+ is also believed to be involved in the induction of the various forms of LTD at this synapse. We used photolysis of caged Ca2+ compounds to test whether a postsynaptic rise in [Ca2+]i is sufficient to induce changes in synaptic transmission at mossy fiber synapses onto rat hippocampal CA3 pyramidal neurons. We were able to elevate postsynaptic [Ca2+]i to approximately 1 microm for a few seconds in pyramidal cell somata and dendrites. We estimate that CA3 pyramidal neurons have approximately fivefold greater endogenous Ca2+ buffer capacity than CA1 neurons, limiting the rise in [Ca2+]i achievable by photolysis. This [Ca2+]i rise induced either a potentiation or a depression at mossy fiber synapses in different preparations. Neither the potentiation nor the depression was accompanied by consistent changes in paired-pulse facilitation, suggesting that these forms of plasticity may be distinct from synaptically induced LTP and LTD at this synapse. Our results are consistent with a postsynaptic locus for the induction of at least some forms of synaptic plasticity at mossy fiber synapses.
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Affiliation(s)
- Jun Wang
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720, USA
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Huang CC, You JL, Lee CC, Hsu KS. Insulin induces a novel form of postsynaptic mossy fiber long-term depression in the hippocampus. Mol Cell Neurosci 2003; 24:831-41. [PMID: 14664829 DOI: 10.1016/s1044-7431(03)00238-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The mechanisms of induction and the site of expression of long-term depression (LTD) at the hippocampal mossy fiber-CA3 synapses are not clear. Here, we show that a brief bath application of insulin induces a novel form of mossy fiber LTD. This insulin-LTD is (1) induced and expressed postsynaptically, (2) entirely independent of synaptic stimulation during insulin application, (3) involving a rise in postsynaptic [Ca(2+)](i) and L-type voltage-activated Ca(2+) channel activation, (4) mechanistically distinct from low-frequency stimulation-induced LTD, (5) dependent on phosphatidylinositol 3-kinase signaling, and (6) associated with a clathrin-mediated endocytotic removal of surface 3-hydroxy-5-methylisoxazole-4-propionic acid receptors from the postsynaptic neurons. Moreover, insulin-LTD is specific to mossy fibers to CA3 pyramidal cell synapses, and is not present at associational commissural synapses. These findings not only support a postsynaptic locus of mossy fiber LTD, but also provide a further link between the AMPA receptor trafficking and the bidirectional expression of long-term synaptic plasticity.
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Affiliation(s)
- Chiung-Chun Huang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan City 701, Taiwan
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