Suppr超能文献

胆囊收缩素表达中间神经元传入减少导致颞叶癫痫小鼠海马 CA2 区去抑制。

Reduced Cholecystokinin-Expressing Interneuron Input Contributes to Disinhibition of the Hippocampal CA2 Region in a Mouse Model of Temporal Lobe Epilepsy.

机构信息

Departments of Neuroscience and Pharmacology, Kavli Institute for Brain Science, Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University Irving Medical Center, New York, New York 10027.

Department of Child & Adolescent Psychiatry, New York University Langone Health, New York, New York 10016.

出版信息

J Neurosci. 2023 Oct 11;43(41):6930-6949. doi: 10.1523/JNEUROSCI.2091-22.2023. Epub 2023 Aug 29.

Abstract

A significant proportion of temporal lobe epilepsy (TLE) patients experience drug-resistant seizures associated with mesial temporal sclerosis, in which there is extensive cell loss in the hippocampal CA1 and CA3 subfields, with a relative sparing of dentate gyrus granule cells and CA2 pyramidal neurons (PNs). A role for CA2 in seizure generation was suggested based on findings of a reduction in CA2 synaptic inhibition (Williamson and Spencer, 1994) and the presence of interictal-like spike activity in CA2 in resected hippocampal tissue from TLE patients (Wittner et al., 2009). We recently found that in the pilocarpine-induced status epilepticus (PILO-SE) mouse model of TLE there was an increase in CA2 intrinsic excitability associated with a loss of CA2 synaptic inhibition. Furthermore, chemogenetic silencing of CA2 significantly reduced seizure frequency, consistent with a role of CA2 in promoting seizure generation and/or propagation (Whitebirch et al., 2022). In the present study, we explored the cellular basis of this inhibitory deficit using immunohistochemical and electrophysiological approaches in PILO-SE male and female mice. We report a widespread decrease in the density of pro-cholecystokinin-immunopositive (CCK) interneurons and a functional impairment of CCK interneuron-mediated inhibition of CA2 PNs. We also found a disruption in the perisomatic perineuronal net in the CA2 stratum pyramidale. Such pathologic alterations may contribute to an enhanced excitation of CA2 PNs and CA2-dependent seizure activity in the PILO-SE mouse model. Impaired synaptic inhibition in hippocampal circuits has been identified as a key feature that contributes to the emergence and propagation of seizure activity in human patients and animal models of temporal lobe epilepsy (TLE). Among the hippocampal subfields, the CA2 region is particularly resilient to seizure-associated neurodegeneration and has been suggested to play a key role in seizure activity in TLE. Here we report that perisomatic inhibition of CA2 pyramidal neurons mediated by cholecystokinin-expressing interneurons is selectively reduced in acute hippocampal slices from epileptic mice. Parvalbumin-expressing interneurons, in contrast, appear relatively conserved in epileptic mice. These findings advance our understanding of the cellular mechanisms underlying inhibitory disruption in hippocampal circuits in a mouse model of spontaneous recurring seizures.

摘要

相当比例的颞叶癫痫(TLE)患者经历耐药性发作,与内侧颞叶硬化有关,其中海马 CA1 和 CA3 亚区广泛丧失细胞,齿状回颗粒细胞和 CA2 锥体神经元相对保留(PNs)。CA2 在发作发生中的作用是基于发现 CA2 突触抑制减少(Williamson 和 Spencer,1994)和 TLE 患者切除海马组织中 CA2 存在发作样尖峰活动(Wittner 等人,2009)。我们最近发现,在匹罗卡品诱导的癫痫持续状态(PILO-SE)小鼠模型中,CA2 内在兴奋性增加与 CA2 突触抑制丧失有关。此外,CA2 的化学遗传沉默显着降低了发作频率,这与 CA2 在促进发作发生和/或传播中的作用一致(Whitebirch 等人,2022)。在本研究中,我们使用 PILO-SE 雄性和雌性小鼠的免疫组织化学和电生理方法探讨了这种抑制缺陷的细胞基础。我们报告了广泛的胆囊收缩素免疫阳性(CCK)中间神经元密度降低,以及 CCK 中间神经元介导的 CA2 PNs 抑制功能障碍。我们还发现 CA2 层锥体中的周质周围网络中断。这种病理改变可能导致 CA2 PNs 的兴奋增强和 PILO-SE 小鼠模型中的 CA2 依赖性发作活动。在人类患者和颞叶癫痫(TLE)动物模型中,海马回路中的突触抑制受损已被确定为促进发作活动出现和传播的关键特征。在海马亚区中,CA2 区对与发作相关的神经退行性变特别具有弹性,并被认为在 TLE 中的发作活动中发挥关键作用。在这里,我们报告说,由胆囊收缩素表达中间神经元介导的 CA2 锥体神经元的周质抑制在来自癫痫小鼠的急性海马切片中选择性降低。相反,表达 Parvalbumin 的中间神经元在癫痫小鼠中似乎相对保守。这些发现提高了我们对自发复发性癫痫小鼠模型中海马回路中抑制破坏的细胞机制的理解。

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍。

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索

文档翻译

学术文献翻译模型,支持多种主流文档格式。

立即体验