Spatial stability over time of brain areas generating fast ripples in the epileptic rat
Spatial stability over time of brain areas generating fast ripples in the epileptic rat
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DOI：
10.1046/j.1528-1157.2003.18503.x
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发表时间：
2003-09-01
期刊：
影响因子：
5.6
通讯作者：
Engel, J
中科院分区：
文献类型：
--
作者：
Bragin, A;Wilson, CL;Engel, J
目的：快速波纹（FRs）是200- 600hz范围内的间隔性、病理性高频振荡，可以在啮齿动物癫痫模型和人类内侧颞叶癫痫中从能够产生自发癫痫发作的边缘区域记录下来。为了评估长时间内产生FR的大脑区域的空间稳定性，我们监测了慢性复发性自发癫痫大鼠的间期FR振荡。方法：对22只大鼠单侧海马内注射kainic酸后进行视频监测，直到自发性行为癫痫发作，然后在海马、齿状回和嗅内皮层植入多个微电极。在每天8小时的记录中进行微电极位置的电生理监测，持续时间为6至98天。结果：在齿状回和内嗅皮质非fir产生区附近的离散局部区域记录了间期FRs。在我们的研究中，间隔期FR振荡的位置保持固定，FR的电生理模式保持不变。在监测期间，最初记录间隔性FR的位点继续显示FR振荡，而最初未记录FR的位点从未显示FR活动。记录间歇FRs的电极接触总数与自发发作发生频率之间存在直接关系（p < 0.0001）。结论：这些结果表明，间期FRs反映了嵌入较少致痫性组织的固定病理底物的异常放电，并且自发发作频率取决于该病理底物的范围和分布。
Purpose: Fast ripples (FRs) are interictal, pathological, high-frequency oscillations in the 200- to 600-Hz range, which can be recorded from limbic regions capable of generating spontaneous seizures in rodent models of epilepsy and in human mesial temporal lobe epilepsy. To evaluate the spatial stability of FR-generating brain areas over long periods, we monitored interictal FR oscillations in rats with chronic recurrent spontaneous seizures.Methods: After unilateral intrahippocampal injection of kainic acid, 22 rats were video monitored until spontaneous behavioral seizures occurred, and then implanted with multiple hippocampal, dentate gyrus, and entorhinal cortex microelectrodes. Electrophysiological monitoring of microelectrode sites was carried Out during daily 8-h recordings for periods ranging from 6 to 98 days.Results: Interictal FRs were recorded from discretely localized areas, adjacent to non-FIR-generating areas in dentate gyrus and entorhinal cortex. The location of interictal FR oscillations remained fixed, and the electrophysiological pattern of FRs remained the same over the time of our study. For the duration of monitoring, sites initially recording interictal FRs continued to display FR oscillations, and sites that initially did not record FRs never demonstrated FR activity. A direct relation was seen between the total number of electrode contacts recording interictal FRs and the frequency of spontaneous seizure generation (p < 0.0001).Conclusions: These results suggest that interictal FRs reflect abnormal discharges from a fixed pathologic substrate imbedded within less-epileptogenic tissue, and that spontaneous seizure frequency is dependent on the extent and distribution of this pathologic substrate.