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PubMed · 8567071

Human epileptic astrocytes exhibit increased gap junction coupling.

S H Lee·S Magge·D D Spencer·H Sontheimer·A H Cornell-Bell
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Abstract

Fluorescence Recovery After Photobleach (FRAP) was used to quantify astrocyte gap junction coupling from tissues surgically resected from medically intractable epilepsy patients. Mesial temporal lobe cases provided hippocampus, surrounding hyperexcitable parahippocampus and normal cortex for culture. Cortical tumor cases yielded astrocytoma proper, cortex margins with normal EEG activity, and hyperexcitable cortex. Cells isolated from cortex surrounding astrocytomas and the parahippocampus surrounding the hippocampus showed an increase in glutamate-induced Ca2+ oscillations and intercellular Ca2+ waves. Gap-junction coupling was more pronounced in cells isolated from hyperexcitable tissue than from normal tissues as judged by their faster and more complete fluorescence recovery from laser bleach [FRAP]. This data suggests that intractable epilepsy may be associated with alterations in glial gap junction coupling.

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AstrocytesAstrocytomaBrain NeoplasmsCalciumCerebral CortexCulture TechniquesElectroencephalographyEpilepsyGap JunctionsGlutamic AcidHumansMagnetic Resonance ImagingMicroscopy, FluorescenceTemporal LobeJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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S H Lee, S Magge, D D Spencer, H Sontheimer, A H Cornell-Bell. 1995. Human epileptic astrocytes exhibit increased gap junction coupling.. https://doi.org/10.1002/glia.440150212

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