2023
Conditional Astrocyte Rac1KO Attenuates Hyperreflexia after Spinal Cord Injury
Benson C, Olson K, Patwa S, Kauer S, King J, Waxman S, Tan A. Conditional Astrocyte Rac1KO Attenuates Hyperreflexia after Spinal Cord Injury. Journal Of Neuroscience 2023, 44: e1670222023. PMID: 37963762, PMCID: PMC10851682, DOI: 10.1523/jneurosci.1670-22.2023.Peer-Reviewed Original ResearchConceptsSpinal cord injuryRate-dependent depressionΑ-motor neuronsGlutamate transporter 1Dendritic spine dysgenesisCord injurySpine dysgenesisDevelopment of SCIMild contusion spinal cord injuryAstrocytic glutamate transporter 1Glial-specific glutamate transporterContusion spinal cord injuryTransporter 1Development of hyperreflexiaMonosynaptic H-reflexDendritic spine densityPre-injury levelSpinal reflex circuitsVentral spinal cordReflex hyperexcitabilityHyperexcitability disordersFunctional recoveryGlutamate clearanceH-reflexVentral hornIncreased astrocytic GLT-1 expression in tripartite synapses is associated with SCI-induced hyperreflexia
Benson C, King J, Kauer S, Waxman S, Tan A. Increased astrocytic GLT-1 expression in tripartite synapses is associated with SCI-induced hyperreflexia. Journal Of Neurophysiology 2023, 130: 1358-1366. PMID: 37877184, PMCID: PMC10972632, DOI: 10.1152/jn.00234.2023.Peer-Reviewed Original ResearchConceptsSpinal cord injuryRate-dependent depressionTripartite synapsesGLT-1Astrocytic GLT-1 expressionChronic neurological complicationsGLT-1 expressionAstrocyte involvementChronic spasticityUninjured shamsNeurological complicationsNeuropathic painHyperexcitability disordersH-reflexPSD-95 proteinReactive astrocytesVentral hornCord injuryMuscle toneAstrocytes' roleSpinal cordSpinal circuitsSynaptic transmissionHyperreflexiaSpasticity
1998
Effects of Glucose Deprivation, Chemical Hypoxia, and Simulated Ischemia on Na+ Homeostasis in Rat Spinal Cord Astrocytes
Rose C, Waxman S, Ransom B. Effects of Glucose Deprivation, Chemical Hypoxia, and Simulated Ischemia on Na+ Homeostasis in Rat Spinal Cord Astrocytes. Journal Of Neuroscience 1998, 18: 3554-3562. PMID: 9570787, PMCID: PMC6793162, DOI: 10.1523/jneurosci.18-10-03554.1998.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsAnimals, NewbornAntimetabolitesAstrocytesBenzofuransCell HypoxiaDeoxyglucoseEnergy MetabolismEnzyme InhibitorsEthers, CyclicExcitatory Amino Acid AgonistsFluorescent DyesFluorides, TopicalGlucoseGlycolysisHomeostasisIschemiaKainic AcidNeurotoxinsOuabainRatsRats, Sprague-DawleySodiumSodium AzideSodium FluorideSodium-Potassium-Exchanging ATPaseSpinal CordTetrodotoxinConceptsSpinal cord astrocytesChemical hypoxiaGlucose deprivationEnergy failureCultured spinal cord astrocytesGlutamatergic agonist kainateGlucose salineGlutamate reuptakeVivo ischemiaSpinal cordGlial functionMetabolic insultsSimulated ischemiaAgonist kainateIschemiaStandard salineAstrocytesSalineHypoxiaIntracellular ion concentrationsGlucose removalExtracellular spaceDeprivationL-lactateReperfusionNovel splice variants of the voltage-sensitive sodium channel alpha subunit
Oh Y, Waxman S. Novel splice variants of the voltage-sensitive sodium channel alpha subunit. Neuroreport 1998, 9: 1267-1272. PMID: 9631410, DOI: 10.1097/00001756-199805110-00002.Peer-Reviewed Original ResearchMeSH KeywordsAlternative SplicingAmino Acid SequenceAnimalsAnimals, NewbornAstrocytesAstrocytomaBrainBucladesineCalcimycinCells, CulturedGenetic VariationMacromolecular SubstancesModels, MolecularMolecular Sequence DataPolymerase Chain ReactionProtein ConformationRatsRats, Sprague-DawleySodium ChannelsSpinal CordUp-RegulationConceptsChannel alpha subunitNeuroblastoma cellsSpinal cord astrocytesB104 neuroblastoma cellsCultured rat astrocytesChannel mRNA expressionNovel splice variantSplice variantsSodium channel alpha subunitAlpha-subunit mRNASpinal cordCerebral astrocytesUnique regulatory pathwaysAlpha subunitRat astrocytesAstrocytesMRNA expressionSubunit mRNAsMicroM A23187Dibutyryl cAMPPremature truncationCellsExpressionRegulatory pathwaysCordAxon Conduction and Survival in CNS White Matter During Energy Deprivation: A Developmental Study
Fern R, Davis P, Waxman S, Ransom B. Axon Conduction and Survival in CNS White Matter During Energy Deprivation: A Developmental Study. Journal Of Neurophysiology 1998, 79: 95-105. PMID: 9425180, DOI: 10.1152/jn.1998.79.1.95.Peer-Reviewed Original ResearchConceptsAnoxia/aglycemiaCompound action potentialWithdrawal of oxygenOptic nerveCNS white matterWhite matterIsolated rat optic nerveEvoked compound action potentialAdult optic nerveOptic nerve functionRat optic nervePostnatal day 10Permanent lossMin of glucoseEnergy deprivationWithdrawal of glucoseGlucose withdrawalNerve functionAstrocytic glycogenAxon conductionHeightened metabolic activityAdult ratsAglycemiaIrreversible injuryNerve
1997
Pharmacological Characterization of Na+ Influx via Voltage-Gated Na+ Channels in Spinal Cord Astrocytes
Rose C, Ransom B, Waxman S. Pharmacological Characterization of Na+ Influx via Voltage-Gated Na+ Channels in Spinal Cord Astrocytes. Journal Of Neurophysiology 1997, 78: 3249-3258. PMID: 9405543, DOI: 10.1152/jn.1997.78.6.3249.Peer-Reviewed Original ResearchConceptsSpinal cordChannel inactivationCultured spinal cordSpinal cord astrocytesEffect of veratridineSodium-binding benzofuranMicroM tetrodotoxinPharmacological characterizationAgonist kainatePharmacological inhibitionTetrodotoxinAstrocytesVeratridineCordMembrane depolarizationKainateImportant functional roleInfluxFunctional roleInhibitionCellsProminent pathwayATPase activityInactivationBaselineRegulation of Na+ channel β1 and β2 subunit mRNA levels in cultured rat astrocytes
Oh Y, Lee Y, Waxman S. Regulation of Na+ channel β1 and β2 subunit mRNA levels in cultured rat astrocytes. Neuroscience Letters 1997, 234: 107-110. PMID: 9364509, DOI: 10.1016/s0304-3940(97)00694-0.Peer-Reviewed Original ResearchConceptsReverse transcription-polymerase chain reactionMRNA levelsSpinal cordCompetitive reverse transcription-polymerase chain reactionQuantitative competitive reverse transcription-polymerase chain reactionSpinal cord astrocytesRat optic nerveDibutyryl cAMPBeta 2 mRNACultured rat astrocytesTranscription-polymerase chain reactionBeta 1 mRNASubunit mRNA levelsNeuroblastoma cell linesOptic nerveChannel β1Cultured astrocytesRat astrocytesCalcium ionophoreAstrocytesBeta 1Chain reactionCell linesCordMRNA
1996
Manipulation of the delayed rectifier Kv1.5 potassium channel in glial cells by antisense oligodeoxynucleotides
Roy M, Saal D, Perney T, Sontheimer H, Waxman S, Kaczmarek L. Manipulation of the delayed rectifier Kv1.5 potassium channel in glial cells by antisense oligodeoxynucleotides. Glia 1996, 18: 177-184. PMID: 8915650, DOI: 10.1002/(sici)1098-1136(199611)18:3<177::aid-glia2>3.0.co;2-x.Peer-Reviewed Original ResearchConceptsGlial cellsKv1.5 channel proteinSpinal cordKv1.5 proteinCultured spinal cordTEA-insensitive currentSpinal cord astrocytesRectifier current densityPotassium channel typesAntisense oligodeoxynucleotide treatmentKv1.5 potassium channelAdult ratsCerebellar slicesChannel proteinsAstrocytesOligodeoxynucleotide treatmentPotassium channelsRectifier currentEndfoot processesSuch treatmentCurrent activationAntisense oligodeoxynucleotidesCordCellsTreatment
1995
Differential Na+ channel β1 subunit mRNA expression in stellate and flat astrocytes cultured from rat cortex and cerebellum: A combined in situ hybridization and immunocytochemistry study
Oh Y, Waxman S. Differential Na+ channel β1 subunit mRNA expression in stellate and flat astrocytes cultured from rat cortex and cerebellum: A combined in situ hybridization and immunocytochemistry study. Glia 1995, 13: 166-173. PMID: 7782102, DOI: 10.1002/glia.440130303.Peer-Reviewed Original ResearchConceptsGFAP-positive astrocytesRat brainChannel beta 1 subunit (Na beta 1) mRNAMRNA expressionBeta 1 mRNA expressionSubunit mRNA expressionBeta 1 mRNABeta 1 subunit mRNARat cortexGranule cellsStellate astrocytesRat astrocytesAstrocytesChannel mRNAImmunocytochemistry methodSubunit mRNAsImmunocytochemistry studiesCerebellumBrainMRNASitu hybridizationRecent studiesDifferential expressionExpressionCells
1994
Type II sodium channels in spinal cord astrocytes in situ: Immunocytochemical observations
Black J, Westenbroek R, Ransom B, Catterall W, Waxman S. Type II sodium channels in spinal cord astrocytes in situ: Immunocytochemical observations. Glia 1994, 12: 219-227. PMID: 7851989, DOI: 10.1002/glia.440120307.Peer-Reviewed Original ResearchConceptsAdult rat spinal cordRat spinal cordOptic nerveSubtype-specific sequencesSpinal cordVentral funiculusSpinal cord white matter tractsSpinal cord white matterSodium channelsSpinal cord astrocytesCord white matterWhite matter tractsType ISodium channel alphaWhite matterAstrocytesNerveImmunocytochemical methodsCordChannel alphaSodium channel IIIsoform expressionDetectable labelingType II sodium channelsImmunocytochemical observationsAstrocyte Na+ channels are required for maintenance of Na+/K(+)-ATPase activity
Sontheimer H, Fernandez-Marques E, Ullrich N, Pappas C, Waxman S. Astrocyte Na+ channels are required for maintenance of Na+/K(+)-ATPase activity. Journal Of Neuroscience 1994, 14: 2464-2475. PMID: 8182422, PMCID: PMC6577452, DOI: 10.1523/jneurosci.14-05-02464.1994.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsAnimals, NewbornAstrocytesAstrocytomaCell LineCells, CulturedElectrophysiologyGanglia, SpinalGliomaMembrane PotentialsModels, BiologicalOuabainRatsRats, Sprague-DawleyRubidiumSodiumSodium ChannelsSodium-Potassium-Exchanging ATPaseStrophanthidinTetrodotoxinTime FactorsTumor Cells, CulturedConceptsEffects of TTXGlial cellsAction potential electrogenesisRat spinal cordPatch-clamp recordingsAstrocyte membrane potentialDose-dependent mannerVoltage-activated channelsAcute blockadeSpinal cordVoltage-activated ion channelsSpecific blockerATPase activityAstrocytesTTXAstrocyte deathAction potentialsUnidirectional influxBlockadeExcitable cellsIon channelsOuabainExtracellular spaceMembrane potentialIon levelsThe expression of rat brain voltage-sensitive Na+ channel mRNAs in astrocytes
Oh Y, Black J, Waxman S. The expression of rat brain voltage-sensitive Na+ channel mRNAs in astrocytes. Brain Research 1994, 23: 57-65. PMID: 8028484, DOI: 10.1016/0169-328x(94)90211-9.Peer-Reviewed Original ResearchConceptsRat brainChannel mRNAChannel subtypesCultured spinal cordSkeletal muscleRat optic nerveNeuronal cell bodiesRegions of CNSSubtype IRat skeletal muscleOptic nervePolymerase chain reactionSpinal cordRat astrocytesDistinct subtypesAstrocytesCell bodiesSubtypesBrainRT-PCRSubtype IIRat tissuesChain reactionRat liverReverse transcription
1993
Molecular dissection of the myelinated axon
Waxman S, Ritchie J. Molecular dissection of the myelinated axon. Annals Of Neurology 1993, 33: 121-136. PMID: 7679565, DOI: 10.1002/ana.410330202.Peer-Reviewed Original ResearchConceptsMyelinated axonsInternodal axon membraneDemyelinated axonsCentral nervous system white matterNervous system white matterRestoration of conductionImportant therapeutic approachSchwann cell processesWhite matter axonsInflux of Ca2Important pathophysiological implicationsGlial cell processesAction potential conductionAxonal excitabilityGlial cellsAnoxic injuryMyelinated fibersTherapeutic approachesAstrocyte processesCell processesPathophysiological implicationsRepetitive firingWhite matterNeurological disordersAction potentials
1992
Chapter 8: The expression of sodium channels in astrocytes in situ and in vitro
Black J, Sontheimer H, Minturn J, Ransom B, Waxman S. Chapter 8: The expression of sodium channels in astrocytes in situ and in vitro. Progress In Brain Research 1992, 94: 89-107. PMID: 1337617, DOI: 10.1016/s0079-6123(08)61742-2.Peer-Reviewed Original ResearchConceptsOptic nerve astrocytesSodium channel expressionChannel expressionSodium channelsOptic nerveSodium current propertiesChannel expression patternsIon channel expressionSimilar electrophysiological propertiesCultured astrocytesAstrocytesElectrophysiological propertiesSodium currentHeterogeneous groupDifferent patternsNerveDifferent subpopulationsExpressionExpression patternsCell-cell interactionsHippocampusA2B5Neurons
1988
The perinodal astrocyte
Black J, Waxman S. The perinodal astrocyte. Glia 1988, 1: 169-183. PMID: 2976037, DOI: 10.1002/glia.440010302.Peer-Reviewed Original Research
1985
Perinodal astrocytic processes at nodes of ranvier in developing normal and glial cell deficient rat spinal cord
Sims T, Waxman S, Black J, Gilmore S. Perinodal astrocytic processes at nodes of ranvier in developing normal and glial cell deficient rat spinal cord. Brain Research 1985, 337: 321-331. PMID: 4027576, DOI: 10.1016/0006-8993(85)90069-1.Peer-Reviewed Original ResearchConceptsPerinodal astrocytic processesLumbar spinal cordSpinal cordGlial cellsAstrocytic processesNodes of RanvierThird postnatal dayRat spinal cordSpinal cord axonsIrradiated spinal cordStages of myelinationAstrocyte involvementVentral funiculusNeuronal elementsPostnatal dayOligodendrocyte populationCentral myelinCordAstrocytesProfound reductionMyelin sheathAxonsRatsNodal axolemmaPresumptive roleGlial proliferation in the irradiated rat spinal cord
Sims T, Waxman S, Gilmore S. Glial proliferation in the irradiated rat spinal cord. Acta Neuropathologica 1985, 68: 169-172. PMID: 4072625, DOI: 10.1007/bf00688641.Peer-Reviewed Original ResearchConceptsSpinal cordRat spinal cordPost-irradiation intervalsGlial proliferationIncorporation of3H-thymidineGlial cellsAdjacent thin sectionsWhite matterThick plastic sectionsCell bodiesMyelin sheathVentral halfCordOf3H-thymidineAstrogliaIrregular outlinePresent studyMitotic cellsCellsPlastic sectionsBundles of filamentsRatsMyelinationOligodendrocytesSpecialization of astrocytic membrane at glia limitans in rat optic nerve: Freeze-fracture observations
Black J, Waxman S. Specialization of astrocytic membrane at glia limitans in rat optic nerve: Freeze-fracture observations. Neuroscience Letters 1985, 55: 371-378. PMID: 4011040, DOI: 10.1016/0304-3940(85)90464-1.Peer-Reviewed Original Research
1984
Freeze-fracture ultrastructure of the perinodal astrocyte and associated glial junctions
Waxman S, Black J. Freeze-fracture ultrastructure of the perinodal astrocyte and associated glial junctions. Brain Research 1984, 308: 77-87. PMID: 6434150, DOI: 10.1016/0006-8993(84)90919-3.Peer-Reviewed Original ResearchPostnatal differentiation of rat optic nerve fibers: Electron microscopic observations on the development of nodes of Ranvier and axoglial relations
Hildebrand C, Waxman S. Postnatal differentiation of rat optic nerve fibers: Electron microscopic observations on the development of nodes of Ranvier and axoglial relations. The Journal Of Comparative Neurology 1984, 224: 25-37. PMID: 6715578, DOI: 10.1002/cne.902240103.Peer-Reviewed Original ResearchConceptsRat optic nerve fibersOptic nerve fibersNerve fibersUnmyelinated optic nerve axonsPostnatal differentiationOptic nerve axonsPerinodal astrocytic processesAxoglial signallingNodes of RanvierVesiculotubular profilesOptic nerveRat pupsCompact myelin sheathAxolemmal undercoatingAstrocytic processesNerve axonsAxonal diameterMyelin sheathAxon segmentsAxonsAxolemmaRanvierDaysElectron microscopic observationsFunctional differentiation