Abstract
Impaired inhibition is thought to be important in temporal lobe epilepsy (TLE), the most common form of epilepsy in adult patients. We report that, in experimental TLE, spontaneous GABAergic inhibition was increased in the soma but reduced in the dendrites of pyramidal neurons. The former resulted from the hyperactivity of somatic projecting interneurons, whereas the latter was probably due to the degeneration of a subpopulation of dendritic projecting interneurons. A deficit in dendritic inhibition could reduce seizure threshold, whereas enhanced somatic inhibition would prevent the continuous occurrence of epileptiform activity.
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Acknowledgements
We thank A.J. Tobin and N.J.K. Tillakaratne for the GAD67 cDNA and D. Diabira for the kainate-lesioned animals. This work was supported by I.N.S.E.R.M and the Simone and Cino del Duca Foundation.
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Cossart, R., Dinocourt, C., Hirsch, J. et al. Dendritic but not somatic GABAergic inhibition is decreased in experimental epilepsy. Nat Neurosci 4, 52–62 (2001). https://doi.org/10.1038/82900
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DOI: https://doi.org/10.1038/82900
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