Anticonvulsant Effects of Transcranial Direct‐current Stimulation (tDCS) in the Rat Cortical Ramp Model of Focal Epilepsy
Purpose: Weak direct currents induce lasting alterations of cortical excitability in animals and humans, which are controlled by polarity, duration of stimulation, and current strength applied. To evaluate its anticonvulsant potential, transcranial direct current stimulation (tDCS) was tested in a m...
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| Veröffentlicht in: | Epilepsia (Copenhagen) 2006-07, Vol.47 (7), p.1216-1224 |
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| creator | Liebetanz, David Klinker, Florian Hering, Diana Koch, Reinhard Nitsche, Michael A. Potschka, Heidrun Löscher, Wolfgang Paulus, Walter Tergau, Frithjof |
| description | Purpose: Weak direct currents induce lasting alterations of cortical excitability in animals and humans, which are controlled by polarity, duration of stimulation, and current strength applied. To evaluate its anticonvulsant potential, transcranial direct current stimulation (tDCS) was tested in a modified cortical ramp‐stimulation model of focal epilepsy.
Methods: The threshold for localized seizure activity (TLS) was determined in freely moving rats by applying a single train of rising bipolar pulses through a unilateral epicranial electrode. After tDCS, TLS was determined repeatedly for 120 min at intervals of 15 min. The first group of animals received two sessions of cathodal tDCS at 100 μA, one for 30 and one for 60 min. A third session consisted of 60 min of anodal tDCS. A second group received cathodal tDCS at 200 μA for 15 and for 30 min, as well as anodal tDCS for 30 min.
Results: Sixty minutes of cathodal tDCS at 100 μA resulted in a TLS increase lasting for ≥2 h. When the intensity was increased to 200 μA, a similar lasting TLS elevation occurred after a stimulation of just 30‐min duration. In contrast, anodal tDCS at identical stimulation durations and current strengths had no significant effect on TLS.
Conclusions: The anticonvulsive effect induced by cathodal tDCS depends on stimulation duration and current strength and may be associated with the induction of alterations of cortical excitability that outlast the actual stimulation. The results lead to the reasonable assumption that cathodal tDCS could evolve as a therapeutic tool in drug‐refractory partial epilepsy. |
| doi_str_mv | 10.1111/j.1528-1167.2006.00539.x |
| format | Article |
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Methods: The threshold for localized seizure activity (TLS) was determined in freely moving rats by applying a single train of rising bipolar pulses through a unilateral epicranial electrode. After tDCS, TLS was determined repeatedly for 120 min at intervals of 15 min. The first group of animals received two sessions of cathodal tDCS at 100 μA, one for 30 and one for 60 min. A third session consisted of 60 min of anodal tDCS. A second group received cathodal tDCS at 200 μA for 15 and for 30 min, as well as anodal tDCS for 30 min.
Results: Sixty minutes of cathodal tDCS at 100 μA resulted in a TLS increase lasting for ≥2 h. When the intensity was increased to 200 μA, a similar lasting TLS elevation occurred after a stimulation of just 30‐min duration. In contrast, anodal tDCS at identical stimulation durations and current strengths had no significant effect on TLS.
Conclusions: The anticonvulsive effect induced by cathodal tDCS depends on stimulation duration and current strength and may be associated with the induction of alterations of cortical excitability that outlast the actual stimulation. The results lead to the reasonable assumption that cathodal tDCS could evolve as a therapeutic tool in drug‐refractory partial epilepsy.</description><identifier>ISSN: 0013-9580</identifier><identifier>EISSN: 1528-1167</identifier><identifier>DOI: 10.1111/j.1528-1167.2006.00539.x</identifier><identifier>PMID: 16886986</identifier><identifier>CODEN: EPILAK</identifier><language>eng</language><publisher>Malden, USA: Blackwell Publishing Inc</publisher><subject>Animals ; Anticonvulsants - pharmacology ; Anticonvulsants - therapeutic use ; Anticonvulsants. Antiepileptics. Antiparkinson agents ; Antiepileptic drugs ; Biological and medical sciences ; Cerebral Cortex - drug effects ; Cerebral Cortex - physiology ; Disease Models, Animal ; Drug Resistance ; Electric Stimulation ; Electric Stimulation Therapy - methods ; Electrodes ; Epilepsies, Partial - drug therapy ; Epilepsies, Partial - etiology ; Epilepsies, Partial - prevention & control ; Epilepsy ; Frontal Lobe - physiology ; Functional Laterality - physiology ; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy ; Male ; Malformations of the nervous system ; Medical sciences ; Nervous system (semeiology, syndromes) ; Neurology ; Neuropharmacology ; Neuroplasticity ; Pharmacology. Drug treatments ; Rat brain ; Rats ; Rats, Wistar ; Transcranial direct current stimulation (tDCS)</subject><ispartof>Epilepsia (Copenhagen), 2006-07, Vol.47 (7), p.1216-1224</ispartof><rights>2006 INIST-CNRS</rights><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c5729-61c3fc993e8b2f3248620b640b8b68d611d3b16dc3a26eeeb67056e1bf0cd9d03</citedby><cites>FETCH-LOGICAL-c5729-61c3fc993e8b2f3248620b640b8b68d611d3b16dc3a26eeeb67056e1bf0cd9d03</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://onlinelibrary.wiley.com/doi/pdf/10.1111%2Fj.1528-1167.2006.00539.x$$EPDF$$P50$$Gwiley$$H</linktopdf><linktohtml>$$Uhttps://onlinelibrary.wiley.com/doi/full/10.1111%2Fj.1528-1167.2006.00539.x$$EHTML$$P50$$Gwiley$$H</linktohtml><link.rule.ids>314,776,780,1411,1427,27901,27902,45550,45551,46384,46808</link.rule.ids><backlink>$$Uhttp://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetail&idt=18031712$$DView record in Pascal Francis$$Hfree_for_read</backlink><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/16886986$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Liebetanz, David</creatorcontrib><creatorcontrib>Klinker, Florian</creatorcontrib><creatorcontrib>Hering, Diana</creatorcontrib><creatorcontrib>Koch, Reinhard</creatorcontrib><creatorcontrib>Nitsche, Michael A.</creatorcontrib><creatorcontrib>Potschka, Heidrun</creatorcontrib><creatorcontrib>Löscher, Wolfgang</creatorcontrib><creatorcontrib>Paulus, Walter</creatorcontrib><creatorcontrib>Tergau, Frithjof</creatorcontrib><title>Anticonvulsant Effects of Transcranial Direct‐current Stimulation (tDCS) in the Rat Cortical Ramp Model of Focal Epilepsy</title><title>Epilepsia (Copenhagen)</title><addtitle>Epilepsia</addtitle><description>Purpose: Weak direct currents induce lasting alterations of cortical excitability in animals and humans, which are controlled by polarity, duration of stimulation, and current strength applied. To evaluate its anticonvulsant potential, transcranial direct current stimulation (tDCS) was tested in a modified cortical ramp‐stimulation model of focal epilepsy.
Methods: The threshold for localized seizure activity (TLS) was determined in freely moving rats by applying a single train of rising bipolar pulses through a unilateral epicranial electrode. After tDCS, TLS was determined repeatedly for 120 min at intervals of 15 min. The first group of animals received two sessions of cathodal tDCS at 100 μA, one for 30 and one for 60 min. A third session consisted of 60 min of anodal tDCS. A second group received cathodal tDCS at 200 μA for 15 and for 30 min, as well as anodal tDCS for 30 min.
Results: Sixty minutes of cathodal tDCS at 100 μA resulted in a TLS increase lasting for ≥2 h. When the intensity was increased to 200 μA, a similar lasting TLS elevation occurred after a stimulation of just 30‐min duration. In contrast, anodal tDCS at identical stimulation durations and current strengths had no significant effect on TLS.
Conclusions: The anticonvulsive effect induced by cathodal tDCS depends on stimulation duration and current strength and may be associated with the induction of alterations of cortical excitability that outlast the actual stimulation. The results lead to the reasonable assumption that cathodal tDCS could evolve as a therapeutic tool in drug‐refractory partial epilepsy.</description><subject>Animals</subject><subject>Anticonvulsants - pharmacology</subject><subject>Anticonvulsants - therapeutic use</subject><subject>Anticonvulsants. Antiepileptics. Antiparkinson agents</subject><subject>Antiepileptic drugs</subject><subject>Biological and medical sciences</subject><subject>Cerebral Cortex - drug effects</subject><subject>Cerebral Cortex - physiology</subject><subject>Disease Models, Animal</subject><subject>Drug Resistance</subject><subject>Electric Stimulation</subject><subject>Electric Stimulation Therapy - methods</subject><subject>Electrodes</subject><subject>Epilepsies, Partial - drug therapy</subject><subject>Epilepsies, Partial - etiology</subject><subject>Epilepsies, Partial - prevention & control</subject><subject>Epilepsy</subject><subject>Frontal Lobe - physiology</subject><subject>Functional Laterality - physiology</subject><subject>Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy</subject><subject>Male</subject><subject>Malformations of the nervous system</subject><subject>Medical sciences</subject><subject>Nervous system (semeiology, syndromes)</subject><subject>Neurology</subject><subject>Neuropharmacology</subject><subject>Neuroplasticity</subject><subject>Pharmacology. Drug treatments</subject><subject>Rat brain</subject><subject>Rats</subject><subject>Rats, Wistar</subject><subject>Transcranial direct current stimulation (tDCS)</subject><issn>0013-9580</issn><issn>1528-1167</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2006</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><recordid>eNqNkcFu1DAQQC1ERbeFX0C-gNpD0rG9cRyJS7XdQqVWRW05W47jCK-SONgOdMWFT-Ab-RIcdkWP4IM9Gr8ZW_MQwgRyktbZJicFFRkhvMwpAM8BClblj8_Q4u_Fc7QAICyrCgGH6CiEDQCUvGQv0CHhQvBK8AX6fj5Eq93wdeqCGiJet63RMWDX4gevhqDTZlWHL6xP-V8_furJe5PA-2j7qVPRugGfxIvV_Sm2A46fDb5TEa-cT21T3Z3qR3zjGtPNLS_dnFuPtjNj2L5EB63qgnm1P4_Rp8v1w-pDdn37_mp1fp3poqRVxolmra4qZkRNW0aXglOo-RJqUXPRcEIaVhPeaKYoN8bUvISCG1K3oJuqAXaM3u76jt59mUyIsrdBm65Tg3FTkFyUhCyZ-CdIoWIgeJFAsQO1dyF408rR2175rSQgZ0NyI2cRchYhZ0PyjyH5mEpf79-Y6t40T4V7JQl4swdUSNNqkwBtwxMngJGS0MS923Hf0jS3__0Buf54lQL2G-qMrTM</recordid><startdate>200607</startdate><enddate>200607</enddate><creator>Liebetanz, David</creator><creator>Klinker, Florian</creator><creator>Hering, Diana</creator><creator>Koch, Reinhard</creator><creator>Nitsche, Michael A.</creator><creator>Potschka, Heidrun</creator><creator>Löscher, Wolfgang</creator><creator>Paulus, Walter</creator><creator>Tergau, Frithjof</creator><general>Blackwell Publishing Inc</general><general>Blackwell</general><scope>IQODW</scope><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>7TK</scope><scope>7X8</scope></search><sort><creationdate>200607</creationdate><title>Anticonvulsant Effects of Transcranial Direct‐current Stimulation (tDCS) in the Rat Cortical Ramp Model of Focal Epilepsy</title><author>Liebetanz, David ; Klinker, Florian ; Hering, Diana ; Koch, Reinhard ; Nitsche, Michael A. ; Potschka, Heidrun ; Löscher, Wolfgang ; Paulus, Walter ; Tergau, Frithjof</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c5729-61c3fc993e8b2f3248620b640b8b68d611d3b16dc3a26eeeb67056e1bf0cd9d03</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2006</creationdate><topic>Animals</topic><topic>Anticonvulsants - pharmacology</topic><topic>Anticonvulsants - therapeutic use</topic><topic>Anticonvulsants. Antiepileptics. Antiparkinson agents</topic><topic>Antiepileptic drugs</topic><topic>Biological and medical sciences</topic><topic>Cerebral Cortex - drug effects</topic><topic>Cerebral Cortex - physiology</topic><topic>Disease Models, Animal</topic><topic>Drug Resistance</topic><topic>Electric Stimulation</topic><topic>Electric Stimulation Therapy - methods</topic><topic>Electrodes</topic><topic>Epilepsies, Partial - drug therapy</topic><topic>Epilepsies, Partial - etiology</topic><topic>Epilepsies, Partial - prevention & control</topic><topic>Epilepsy</topic><topic>Frontal Lobe - physiology</topic><topic>Functional Laterality - physiology</topic><topic>Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy</topic><topic>Male</topic><topic>Malformations of the nervous system</topic><topic>Medical sciences</topic><topic>Nervous system (semeiology, syndromes)</topic><topic>Neurology</topic><topic>Neuropharmacology</topic><topic>Neuroplasticity</topic><topic>Pharmacology. Drug treatments</topic><topic>Rat brain</topic><topic>Rats</topic><topic>Rats, Wistar</topic><topic>Transcranial direct current stimulation (tDCS)</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Liebetanz, David</creatorcontrib><creatorcontrib>Klinker, Florian</creatorcontrib><creatorcontrib>Hering, Diana</creatorcontrib><creatorcontrib>Koch, Reinhard</creatorcontrib><creatorcontrib>Nitsche, Michael A.</creatorcontrib><creatorcontrib>Potschka, Heidrun</creatorcontrib><creatorcontrib>Löscher, Wolfgang</creatorcontrib><creatorcontrib>Paulus, Walter</creatorcontrib><creatorcontrib>Tergau, Frithjof</creatorcontrib><collection>Pascal-Francis</collection><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>Neurosciences Abstracts</collection><collection>MEDLINE - Academic</collection><jtitle>Epilepsia (Copenhagen)</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Liebetanz, David</au><au>Klinker, Florian</au><au>Hering, Diana</au><au>Koch, Reinhard</au><au>Nitsche, Michael A.</au><au>Potschka, Heidrun</au><au>Löscher, Wolfgang</au><au>Paulus, Walter</au><au>Tergau, Frithjof</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Anticonvulsant Effects of Transcranial Direct‐current Stimulation (tDCS) in the Rat Cortical Ramp Model of Focal Epilepsy</atitle><jtitle>Epilepsia (Copenhagen)</jtitle><addtitle>Epilepsia</addtitle><date>2006-07</date><risdate>2006</risdate><volume>47</volume><issue>7</issue><spage>1216</spage><epage>1224</epage><pages>1216-1224</pages><issn>0013-9580</issn><eissn>1528-1167</eissn><coden>EPILAK</coden><abstract>Purpose: Weak direct currents induce lasting alterations of cortical excitability in animals and humans, which are controlled by polarity, duration of stimulation, and current strength applied. To evaluate its anticonvulsant potential, transcranial direct current stimulation (tDCS) was tested in a modified cortical ramp‐stimulation model of focal epilepsy.
Methods: The threshold for localized seizure activity (TLS) was determined in freely moving rats by applying a single train of rising bipolar pulses through a unilateral epicranial electrode. After tDCS, TLS was determined repeatedly for 120 min at intervals of 15 min. The first group of animals received two sessions of cathodal tDCS at 100 μA, one for 30 and one for 60 min. A third session consisted of 60 min of anodal tDCS. A second group received cathodal tDCS at 200 μA for 15 and for 30 min, as well as anodal tDCS for 30 min.
Results: Sixty minutes of cathodal tDCS at 100 μA resulted in a TLS increase lasting for ≥2 h. When the intensity was increased to 200 μA, a similar lasting TLS elevation occurred after a stimulation of just 30‐min duration. In contrast, anodal tDCS at identical stimulation durations and current strengths had no significant effect on TLS.
Conclusions: The anticonvulsive effect induced by cathodal tDCS depends on stimulation duration and current strength and may be associated with the induction of alterations of cortical excitability that outlast the actual stimulation. The results lead to the reasonable assumption that cathodal tDCS could evolve as a therapeutic tool in drug‐refractory partial epilepsy.</abstract><cop>Malden, USA</cop><pub>Blackwell Publishing Inc</pub><pmid>16886986</pmid><doi>10.1111/j.1528-1167.2006.00539.x</doi><tpages>9</tpages><oa>free_for_read</oa></addata></record> |
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| subjects | Animals Anticonvulsants - pharmacology Anticonvulsants - therapeutic use Anticonvulsants. Antiepileptics. Antiparkinson agents Antiepileptic drugs Biological and medical sciences Cerebral Cortex - drug effects Cerebral Cortex - physiology Disease Models, Animal Drug Resistance Electric Stimulation Electric Stimulation Therapy - methods Electrodes Epilepsies, Partial - drug therapy Epilepsies, Partial - etiology Epilepsies, Partial - prevention & control Epilepsy Frontal Lobe - physiology Functional Laterality - physiology Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy Male Malformations of the nervous system Medical sciences Nervous system (semeiology, syndromes) Neurology Neuropharmacology Neuroplasticity Pharmacology. Drug treatments Rat brain Rats Rats, Wistar Transcranial direct current stimulation (tDCS) |
| title | Anticonvulsant Effects of Transcranial Direct‐current Stimulation (tDCS) in the Rat Cortical Ramp Model of Focal Epilepsy |
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