Epilepsy Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy.
Epilepsy Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy.
Neurobiol Dis. 2023 Mar;178:106007. doi: 10.1016/j.nbd.2023.106007. Epub 2023 Jan 20.
Epilepsies affecting the limbic regions are common and generate seizures often resistant to pharmacological treatment. Clinical evidence demonstrates that diverse regions of the mesial portion of the temporal lobe participate in limbic seizures; these include the hippocampus, the entorhinal, perirhinal and parahippocampal regions and the piriform cortex. The network mechanisms involved in the generation of olfactory-limbic epileptiform patterns will be here examined, with particular emphasis on acute interictal and ictal epileptiform discharges obtained by treatment with pro-convulsive drugs and by high-frequency stimulations on in vitro preparations, such as brain slices and the isolated guinea pig brain. The interactions within olfactory-limbic circuits can be summarized as follows: independent, region-specific seizure-like events (SLE) are generated in the olfactory and in the limbic cortex; SLEs generated in the hippocampal-parahippocampal regions tend to remain within these areas; the perirhinal region controls the neocortical propagation and the generalization of limbic seizures; interictal spiking in the olfactory regions prevents the invasion by SLEs generated in limbic regions. The potential relevance of these observations for human focal epilepsy is discussed.
影响边缘区域的癫痫很常见，且常对药物治疗产生抗性。临床证据表明，颞叶内侧的多个区域参与了边缘性癫痫发作，包括海马体、内嗅皮层、旁嗅皮层和海马旁回以及梨状皮层。本文将在此检查与嗅觉-边缘性癫痫样模式生成相关的网络机制，特别强调了通过致惊厥药物治疗和在体外制剂（如脑切片和分离的豚鼠脑）上进行高频刺激获得的急性发作间期和发作期癫痫样放电。嗅觉-边缘回路中的相互作用可以概括如下：在嗅觉和边缘皮质中会产生独立的、具有区域特异性的癫痫样事件（SLE）；在海马体-海马旁回区域中产生的 SLE 往往会局限于这些区域内；旁嗅皮层控制着新皮层的传播和边缘性癫痫发作的泛化；嗅觉区域的发作间期尖峰放电可防止边缘区域产生的 SLE 入侵。讨论了这些观察结果对人类局灶性癫痫的潜在相关性。
