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Collins HM, Pinacho R, Tam SKE, Sharp T, Bannerman DM, Peirson SN. Continuous home cage monitoring of activity and sleep in mice during repeated paroxetine treatment and discontinuation. Psychopharmacology (Berl) 2023; 240:2403-2418. [PMID: 37584734 PMCID: PMC10593620 DOI: 10.1007/s00213-023-06442-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 07/27/2023] [Indexed: 08/17/2023]
Abstract
RATIONALE Non-invasive home cage monitoring is emerging as a valuable tool to assess the effects of experimental interventions on mouse behaviour. A field in which these techniques may prove useful is the study of repeated selective serotonin reuptake inhibitor (SSRI) treatment and discontinuation. SSRI discontinuation syndrome is an under-researched condition that includes the emergence of sleep disturbances following treatment cessation. OBJECTIVES We used passive infrared (PIR) monitoring to investigate changes in activity, sleep, and circadian rhythms during repeated treatment with the SSRI paroxetine and its discontinuation in mice. METHODS Male mice received paroxetine (10 mg/kg/day, s.c.) for 12 days, then were swapped to saline injections for a 13 day discontinuation period and compared to mice that received saline injections throughout. Mice were continuously tracked using the Continuous Open Mouse Phenotyping of Activity and Sleep Status (COMPASS) system. RESULTS Repeated paroxetine treatment reduced activity and increased behaviourally-defined sleep in the dark phase. These effects recovered to saline-control levels within 24 h of paroxetine cessation, yet there was also evidence of a lengthening of sleep bouts in the dark phase for up to a week following discontinuation. CONCLUSIONS This study provides the first example of how continuous non-invasive home cage monitoring can be used to detect objective behavioural changes in activity and sleep during and after drug treatment in mice. These data suggest that effects of paroxetine administration reversed soon after its discontinuation but identified an emergent change in sleep bout duration, which could be used as a biomarker in future preclinical studies to prevent or minimise SSRI discontinuation symptoms.
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Affiliation(s)
- Helen M Collins
- University Department of Pharmacology, Oxford, UK
- University Department of Experimental Psychology, Oxford, UK
| | - Raquel Pinacho
- University Department of Pharmacology, Oxford, UK
- University Department of Experimental Psychology, Oxford, UK
| | - S K Eric Tam
- Sleep and Circadian Neuroscience Institute (SCNi), Nuffield Department of Clinical Neurosciences, Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford, OX1 3QU, UK
| | - Trevor Sharp
- University Department of Pharmacology, Oxford, UK
| | | | - Stuart N Peirson
- Sleep and Circadian Neuroscience Institute (SCNi), Nuffield Department of Clinical Neurosciences, Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford, OX1 3QU, UK.
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Drysdale ND, Matthews E, Schuetz E, Pan E, McNamara JO. Intravenous kainic acid induces status epilepticus and late onset seizures in mice. Epilepsy Res 2021; 178:106816. [PMID: 34808484 DOI: 10.1016/j.eplepsyres.2021.106816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 10/14/2021] [Accepted: 11/11/2021] [Indexed: 11/19/2022]
Abstract
We set out to establish a novel model of temporal lobe epilepsy (TLE) in a mouse. We sought to induce TLE through the injection of kainic acid (KA) into the tail vein with subsequent development of status epilepticus (SE). Using C57BL/6 mice, we implanted hippocampal EEG recording electrodes before or after injection of KA or phosphate buffered saline (PBS). Video and EEG analysis were conducted to evaluate for SE and development of recurrent seizures, the hallmark of TLE. All mice injected with KA developed SE while those who were injected with PBS did not. Of the animals injected with KA monitored for recurrent seizures following SE, 33% developed spontaneous recurrent seizures while those injected with PBS did not. Injection of KA through the tail vein of a mouse reliably and rapidly induces SE which remits spontaneously and leads to the development of TLE in a subset of mice.
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Affiliation(s)
| | | | | | | | - James O McNamara
- Department of Neurobiology, USA; Department of Neurology, USA; Department of Pharmacology and Molecular Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA.
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Zhong Y, Wang Y, He Z, Lin Z, Pang N, Niu L, Guo Y, Pan M, Meng L. Closed-loop wearable ultrasound deep brain stimulation system based on EEG in mice. J Neural Eng 2021; 18. [PMID: 34388739 DOI: 10.1088/1741-2552/ac1d5c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 08/13/2021] [Indexed: 01/19/2023]
Abstract
Objective. Epilepsy is one of the most common severe brain disorders. Ultrasound deep brain stimulation (UDBS) has shown a potential capability to suppress seizures. However, because seizures occur sporadically, it is necessary to develop a closed-loop system to suppress them. Therefore, we developed a closed-loop wearable UDBS system that delivers ultrasound to the hippocampus to suppress epileptic seizures.Approach.Mice were intraperitoneally injected with 10 mg kg-1kainic acid and divided into sham and UDBS groups. Epileptic seizures were detected by applying both long short-term memory (LSTM) and bidirectional LSTM (BILSTM) networks according to EEG signal characteristics. When epileptic seizures were detected, the closed-loop UDBS system automatically activated a trigger switch to stimulate the hippocampus for 10 min and continuously record EEG signals until 20 min after ultrasonic stimulation. EEG signals were analyzed using the MATLAB software. After EEG recording, we observed the survival rate of the experimental mice for 72 h.Main results.The BiLSTM network was found to have preferable classification performance over the LSTM network. The closed-loop UDBS system with BiLSTM could automatically detect epileptic seizures using EEG signals and effectively reduce epileptic EEG power spectral density and seizure duration by 10.73%, eventually improving the survival rate of early epileptic mice from 67.57% in the sham group to 88.89% in the UDBS group.Significance.The closed-loop UDBS system developed in this study could be an effective clinical tool for the control of epilepsy.
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Affiliation(s)
- Yongsheng Zhong
- Neurosurgery Center, Department of Functional Neurosurgery, The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China on Diagnosis and Treatment of Cerebrovascular Disease, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, The Neurosurgery Institute of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, People's Republic of China.,Institute of Biomedical and Health engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen 518055, People's Republic of China
| | - Yibo Wang
- Institute of Biomedical and Health engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen 518055, People's Republic of China
| | - Zhuoyi He
- Neurosurgery Center, Department of Functional Neurosurgery, The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China on Diagnosis and Treatment of Cerebrovascular Disease, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, The Neurosurgery Institute of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, People's Republic of China
| | - Zhengrong Lin
- Institute of Biomedical and Health engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen 518055, People's Republic of China
| | - Na Pang
- Institute of Biomedical and Health engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen 518055, People's Republic of China
| | - Lili Niu
- Institute of Biomedical and Health engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen 518055, People's Republic of China
| | - Yanwu Guo
- Neurosurgery Center, Department of Functional Neurosurgery, The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China on Diagnosis and Treatment of Cerebrovascular Disease, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, The Neurosurgery Institute of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, People's Republic of China
| | - Min Pan
- Department of Ultrasound, Shenzhen Hospital (Futian) of Guangzhou University of Chinese Medicine, Shenzhen 518034, People's Republic of China
| | - Long Meng
- Institute of Biomedical and Health engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen 518055, People's Republic of China
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Yuskaitis CJ, Rossitto L, Groff KJ, Dhamne SC, Zhang B, Lalani LK, Singh AK, Rotenberg A, Sahin M. Factors influencing the acute pentylenetetrazole-induced seizure paradigm and a literature review. Ann Clin Transl Neurol 2021; 8:1388-1397. [PMID: 34102033 PMCID: PMC8283168 DOI: 10.1002/acn3.51375] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/23/2021] [Accepted: 04/14/2021] [Indexed: 01/18/2023] Open
Abstract
OBJECTIVE To confirm the critical factors affecting seizure susceptibility in acute pentylenetetrazole (PTZ) mouse epilepsy models and evaluate the prior literature for these factors. METHODS Serial cohorts of wild-type mice administered intraperitoneal (IP)-PTZ were aggregated and analyzed by multivariate logistic regression for the effect of sex, age, background strain, dose, and physiologic stress (i.e., EEG implantation and/or single-housing) on seizure response. We assessed the reporting of these factors in a comprehensive literature review over the last 10 years (2010-2020). RESULTS We conducted aggregated analysis of pooled data of 307 mice (220 C57BL/6J mice and 87 mixed background mice; 202 males, 105 females) with median age of 10 weeks (range: 6-49 weeks) with acute PTZ injection (dose range 40-65 mg/kg). Significance in multivariate analysis was found between seizures and increased PTZ dose (odds ratio (OR) 1.149, 95% confidence interval (CI) 1.102-1.205), older age (OR 1.1, 95% CI 1.041-1.170), physiologic stress (OR 17.36, 95% CI 7.349-44.48), and mixed background strain (OR 0.4725, 95% CI 0.2315-0.9345). Literature review identified 97 papers using acute PTZ-seizure models. Age, housing, sex, and background were omitted by 61% (59/97), 51% (49/97), 18% (17/97), and 8% (8/97) papers, respectively. Only 17% of publications specified all four factors (16/97). INTERPRETATION Our analysis and literature review demonstrate a critical gap in standardization of acute PTZ-induced seizure paradigm in mice. We recommend that future studies specify and control for age, background strain, sex, and housing conditions of experimental animals.
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Affiliation(s)
- Christopher J. Yuskaitis
- F.M. Kirby Neurobiology CenterBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
- Department of NeurologyBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
- Division of Epilepsy and Clinical Neurophysiology and Epilepsy Genetics ProgramBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
| | - Leigh‐Ana Rossitto
- F.M. Kirby Neurobiology CenterBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
| | - Karenna J. Groff
- F.M. Kirby Neurobiology CenterBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
| | - Sameer C. Dhamne
- F.M. Kirby Neurobiology CenterBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
| | - Bo Zhang
- Department of NeurologyBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
- Biostatistics and Research Design CenterInstitutional Centers for Clinical and Translational ResearchBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
| | - Lahin K. Lalani
- F.M. Kirby Neurobiology CenterBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
- Rosamund Stone Zander Translational Neuroscience CenterBoston Children’s HospitalBostonMassachusetts02115USA
| | - Achint K. Singh
- F.M. Kirby Neurobiology CenterBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
- Rosamund Stone Zander Translational Neuroscience CenterBoston Children’s HospitalBostonMassachusetts02115USA
| | - Alexander Rotenberg
- F.M. Kirby Neurobiology CenterBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
- Department of NeurologyBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
- Division of Epilepsy and Clinical Neurophysiology and Epilepsy Genetics ProgramBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
- Neuromodulation ProgramDepartment of NeurologyBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
| | - Mustafa Sahin
- F.M. Kirby Neurobiology CenterBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
- Department of NeurologyBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts02115USA
- Rosamund Stone Zander Translational Neuroscience CenterBoston Children’s HospitalBostonMassachusetts02115USA
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Meningeal Lymphangiogenesis and Enhanced Glymphatic Activity in Mice with Chronically Implanted EEG Electrodes. J Neurosci 2020; 40:2371-2380. [PMID: 32047056 DOI: 10.1523/jneurosci.2223-19.2020] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 12/27/2019] [Accepted: 01/22/2020] [Indexed: 12/26/2022] Open
Abstract
Chronic electroencephalography (EEG) is a widely used tool for monitoring cortical electrical activity in experimental animals. Although chronic implants allow for high-quality, long-term recordings in preclinical studies, the electrodes are foreign objects and might therefore be expected to induce a local inflammatory response. We here analyzed the effects of chronic cranial electrode implantation on glymphatic fluid transport and in provoking structural changes in the meninges and cerebral cortex of male and female mice. Immunohistochemical analysis of brain tissue and dura revealed reactive gliosis in the cortex underlying the electrodes and extensive meningeal lymphangiogenesis in the surrounding dura. Meningeal lymphangiogenesis was also evident in mice prepared with the commonly used chronic cranial window. Glymphatic influx of a CSF tracer was significantly enhanced at 30 d postsurgery in both awake and ketamine-xylazine anesthetized mice with electrodes, supporting the concept that glymphatic influx and intracranial lymphatic drainage are interconnected. Altogether, the experimental results provide clear evidence that chronic implantation of EEG electrodes is associated with significant changes in the brain's fluid transport system. Future studies involving EEG recordings and chronic cranial windows must consider the physiological consequences of cranial implants, which include glial scarring, meningeal lymphangiogenesis, and increased glymphatic activity.SIGNIFICANCE STATEMENT This study shows that implantation of extradural electrodes provokes meningeal lymphangiogenesis, enhanced glymphatic influx of CSF, and reactive gliosis. The analysis based on CSF tracer injection in combination with immunohistochemistry showed that chronically implanted electroencephalography electrodes were surrounded by lymphatic sprouts originating from lymphatic vasculature along the dural sinuses and the middle meningeal artery. Likewise, chronic cranial windows provoked lymphatic sprouting. Tracer influx assessed in coronal slices was increased in agreement with previous reports identifying a close association between glymphatic activity and the meningeal lymphatic vasculature. Lymphangiogenesis in the meninges and altered glymphatic fluid transport after electrode implantation have not previously been described and adds new insights to the foreign body response of the CNS.
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Jankovic MJ, Kapadia PP, Krishnan V. Home-cage monitoring ascertains signatures of ictal and interictal behavior in mouse models of generalized seizures. PLoS One 2019; 14:e0224856. [PMID: 31697745 PMCID: PMC6837443 DOI: 10.1371/journal.pone.0224856] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 10/23/2019] [Indexed: 11/25/2022] Open
Abstract
Epilepsy is a significant contributor to worldwide disability. In epilepsy, disability can be broadly divided into two components: ictal (pertaining to the burden of unpredictable seizures and associated medical complications including death) and interictal (pertaining to more pervasive debilitating changes in cognitive and emotional behavior). In this study, we objectively and noninvasively appraise aspects of ictal and interictal behavior in mice using instrumented home-cage chambers designed to assay kinematic and appetitive behavioral measures. Through daily intraperitoneal injections of the chemoconvulsant pentylenetetrazole (PTZ) applied to C57BL/6J mice, we coordinately measure how “behavioral severity” (complex dynamic changes in movement and sheltering behavior) and convulsive severity (latency and occurrence of convulsive seizures) evolve or kindle with repeated injections. By closely studying long epochs between PTZ injections, we identify an interictal syndrome of nocturnal hypoactivity and increased sheltering behavior which remits with the cessation of seizure induction. We observe elements of this interictal behavioral syndrome in seizure-prone DBA/2J mice and in mice with a pathogenic Scn1a mutation (modeling Dravet syndrome). Through analyzing their responses to PTZ, we illustrate how convulsive severity and “behavioral” severity are distinct and independent aspects of the overall severity of a PTZ-induced seizure. Our results illustrate the utility of an ethologically centered automated approach to quantitatively appraise murine expressions of disability in mouse models of seizures and epilepsy. In doing so, this study highlights the very unique psychopharmacological profile of PTZ.
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Affiliation(s)
- Miranda J. Jankovic
- Department of Neurology, Baylor College of Medicine, Houston, TX, United States of America
| | - Paarth P. Kapadia
- Department of Neurology, Baylor College of Medicine, Houston, TX, United States of America
| | - Vaishnav Krishnan
- Department of Neurology, Baylor College of Medicine, Houston, TX, United States of America
- * E-mail:
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Rizwan G, Sabetghadam A, Wu C, Liu J, Zhang L, Reid AY. Increased seizure susceptibility in a mouse model of neurofibromatosis type 1. Epilepsy Res 2019; 156:106190. [PMID: 31445228 DOI: 10.1016/j.eplepsyres.2019.106190] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 08/05/2019] [Accepted: 08/12/2019] [Indexed: 11/27/2022]
Abstract
Neurofibromatosis type 1 (NF1) is a neurocutaneous disorder linked to higher rates of epilepsy as compared with the general population. Although some epilepsy cases in NF1 are related to intracranial lesions, epileptogenic lesions are not always identified. It is unknown whether the genetic mutation itself, which leads to lower levels of the tumor suppressor protein neurofibromin, alters seizure susceptibility. The purpose of this research was to determine whether Nf1+/- mice have altered seizure susceptibility to the chemical convulsants kainic acid and pilocarpine. Young adult Nf1+/- or WT control (Nf1+/+) mice were injected with either 20 mg/kg kainic acid or scopolamine 1 mg/kg and pilocarpine 300 mg/kg and assessed for various behavioral seizure parameters. Another subset of mice were implanted with intracranial electrodes and injected with 10 mg/kg kainic acid for electrographic seizure testing. Histological analyses were performed one week after kainic acid challenge to assess hippocampal damage. A higher proportion of Nf1+/- mice had behavioral seizures after kainic acid or pilocarpine challenge, with shorter seizure latency, longer seizure duration, and higher Racine scores compared to WT mice. Nf1+/- and WT mice with severe behavioral seizures demonstrated similar levels of hippocampal damage. EEG recordings confirmed decreased seizure latency and longer seizure duration in response to KA in the Nf1+/- group. These data demonstrate increased seizure susceptibility in a mouse model of NF1 and support the use of the Nf1+/- mouse for further investigations into the mechanistic link between NF1 and seizures.
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Affiliation(s)
- Gohar Rizwan
- University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C 1A4, Canada.
| | - Azadeh Sabetghadam
- Krembil Research Institute, University Health Network, 60 Leonard Avenue, Toronto, Ontario, M5T 0S8, Canada.
| | - Chiping Wu
- Krembil Research Institute, University Health Network, 60 Leonard Avenue, Toronto, Ontario, M5T 0S8, Canada.
| | - Jackie Liu
- Krembil Research Institute, University Health Network, 60 Leonard Avenue, Toronto, Ontario, M5T 0S8, Canada.
| | - Liang Zhang
- Krembil Research Institute, University Health Network, 60 Leonard Avenue, Toronto, Ontario, M5T 0S8, Canada; Department of Medicine (Neurology), University of Toronto, Toronto, Ontario, Canada.
| | - Aylin Y Reid
- Krembil Research Institute, University Health Network, 60 Leonard Avenue, Toronto, Ontario, M5T 0S8, Canada; Department of Medicine (Neurology), University of Toronto, Toronto, Ontario, Canada.
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Whitmire LE, Ling L, Bugay V, Carver CM, Timilsina S, Chuang HH, Jaffe DB, Shapiro MS, Cavazos JE, Brenner R. Downregulation of KCNMB4 expression and changes in BK channel subtype in hippocampal granule neurons following seizure activity. PLoS One 2017; 12:e0188064. [PMID: 29145442 PMCID: PMC5690595 DOI: 10.1371/journal.pone.0188064] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 10/31/2017] [Indexed: 11/25/2022] Open
Abstract
A major challenge is to understand maladaptive changes in ion channels that sets neurons on a course towards epilepsy development. Voltage- and calcium-activated K+ (BK) channels contribute to early spike timing in neurons, and studies indicate that the BK channel plays a pathological role in increasing excitability early after a seizure. Here, we have investigated changes in BK channels and their accessory β4 subunit (KCNMB4) in dentate gyrus (DG) granule neurons of the hippocampus, key neurons that regulate excitability of the hippocampus circuit. Two days after pilocarpine-induced seizures, we found that the predominant effect is a downregulation of the β4 accessory subunit mRNA. Consistent with reduced expression, single channel recording and pharmacology indicate a switch in the subtype of channels expressed; from iberiotoxin-resistant, type II BK channels (BK α/β4) that have higher channel open probability and slow gating, to iberiotoxin-sensitive type I channels (BK α alone) with low open probability and faster gating. The switch to a majority of type I channel expression following seizure activity is correlated with a loss of BK channel function on spike threshold while maintaining the channel’s contribution to increased early spike frequency. Using heterozygous β4 knockout mice, we find reduced expression is sufficient to increase seizure sensitivity. We conclude that seizure-induced downregulation of KCNMB4 is an activity dependent mechanism that increases the excitability of DG neurons. These novel findings indicate that BK channel subtypes are not only defined by cell-specific expression, but can also be plastic depending on the recent history of neuronal excitability.
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Affiliation(s)
- Luke E. Whitmire
- Department of Cell and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Ling Ling
- Department of Cell and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Vladslav Bugay
- Department of Cell and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Chase M. Carver
- Department of Cell and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Santosh Timilsina
- Department of Cell and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Hui-Hsiu Chuang
- Department of Cell and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - David B. Jaffe
- Department of Biology, University of Texas at San Antonio, San Antonio, Texas, United States of America
| | - Mark S. Shapiro
- Department of Cell and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Jose E. Cavazos
- Neurology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Robert Brenner
- Department of Cell and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- * E-mail:
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