Comparative studies of the GABAergic modulation of oscillations in neuron activity in the medial septal area were performed on living brain slices from healthy guinea pigs and animals with a model of chronic temporal epilepsy. Burst activity persisted only in pacemakers on administration of GABA in both groups of animals. The effectiveness of GABA on rhythmic neurons was sharply reduced in animals with epilepsy. In controls, cells maintaining oscillatory activity showed significant reductions in burst frequency on exposure to GABA, while burst frequency increased sharply in epileptic animals. Blockade of GABAergic receptors revealed impairment to tonic GABAergic intraseptal influences and a significant decrease in blocker efficacy in epilepsy. This report provides the first demonstration of impairments to the functional of the septal GABAergic system in temporal epilepsy, this being a possible cause for the sharp changes seen in the oscillatory properties of septal neurons. These data contribute to our understanding of the mechanisms of development of temporal epilepsy.
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Translated from Zhurnal Vysshei Nervnoi Deyatel’nosti imeni I. P. Pavlova, Vol. 61, No. 3, pp. 377–382, May–June, 2011.
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Malkov, A.E., Popova, I.Y. GABAergic Modulation of Oscillatory Activity in the Medial Septal Area in Epilepsy. Neurosci Behav Physi 42, 1055–1059 (2012). https://doi.org/10.1007/s11055-012-9678-8
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DOI: https://doi.org/10.1007/s11055-012-9678-8