Operative GABAergic inhibition in hippocampal CA1 pyramidal neurons in experimental epilepsy
Operative GABAergic inhibition in hippocampal CA1 pyramidal neurons in experimental epilepsy
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DOI：
10.1073/pnas.94.22.12151
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发表时间：
1997-10-28
影响因子：
11.1
通讯作者：
Bernard, C
中科院分区：
文献类型：
--
作者：
Esclapez, M;Hirsch, JC;Bernard, C
在红藻氨酸或匹罗卡品治疗的大鼠颞叶癫痫模型的海马片上，进行了CA1中间神经元和锥体细胞的膜片钳记录。我们报道，在颞叶癫痫中，锥体神经元中的GABA能抑制仍然起作用，因为：(I)自发GABA能电流的频率与对照组相似，(Ii)局灶性电刺激中间神经元引起超极化，阻止动作电位的产生。在中间神经元和锥体细胞的配对记录中，记录到了同步的发作间活动。此外，在发作间期放电期间，锥体细胞中存在大的网络驱动的GABA能抑制性突触后电流。A型GABA拮抗剂荷包牡丹碱可延长发作间期放电的持续时间。我们的结论是，在这些实验模型中，GABA能抑制仍然存在并发挥作用，而且抑制的主要缺陷并不在于GABA能中间神经元与其谷氨酸能输入完全断开。
Patch-clamp recordings of CA1 interneurons and pyramidal cells were performed in hippocampal slices from kainate-or pilocarpine-treated rat models of temporal lobe epilepsy. We report that gamma-aminobutyric acid (GABA)ergic inhibition in pyramidal neurons is still functional in temporal lobe epilepsy because: (i) the frequency of spontaneous GABAergic currents is similar to that of control and (ii) focal electrical stimulation of interneurons evokes a hyperpolarization that prevents the generation of action potentials. In paired recordings of interneurons and pyramidal cells, synchronous interictal activities were recorded. Furthermore, large network-driven GABAergic inhibitory postsynaptic currents were present in pyramidal cells during interictal discharges. The duration of these interictal discharges was increased by the GABA type A antagonist bicuculline. We conclude that GABAergic inhibition is still present and functional in these experimental models and that the principal defect of inhibition does not lie in a complete disconnection of GABAergic interneurons from their glutamatergic inputs.