Are cytomegalic neurons and balloon cells generators of epileptic activity in pediatric cortical dysplasia?
Are cytomegalic neurons and balloon cells generators of epileptic activity in pediatric cortical dysplasia?
复制标题
DOI：
10.1111/j.1528-1167.2005.01013.x
复制
发表时间：
2005-01-01
期刊：
影响因子：
5.6
通讯作者：
Mathern, TW
中科院分区：
文献类型：
--
作者：
Cepeda, C;André, VM;Mathern, TW
目的：严重皮质发育不良（CD）的特点是存在细胞巨大的神经元和气球细胞。这些异常细胞可能参与癫痫活动的产生。本研究的目的是形态学和电生理特征的细胞在儿科CD tissue.Methods：我们使用红外视频显微镜可视化正常和异常出现的细胞。为了表征电生理特性，我们使用全细胞膜片钳记录从42例儿童CD（年龄0.2-14岁）的组织切片。移液管含有biocytin用于测定的形态features.Results：约25%的记录细胞显示形态差异与正常出现的锥体神经元相比，并分为如下：不成熟，方向错误，畸形，cytomegalic，和气球细胞。未成熟细胞显示发育中神经元的典型电生理膜特性。定向错误的锥体神经元和具有畸形过程的锥体神经元表现出与正常锥体神经元相似的特性。相比之下，巨细胞神经元和气球细胞显示异常的膜特性。气球细胞有一个非常高的输入电阻，缺乏电压门控Na+和Ca 2+电流。cytomegalic神经元有一个非常高的膜电容，非常低的输入电阻，并表现出过度兴奋的迹象，作为例证尖峰的发生重复，缓慢失活Ca 2+时depolarized.Conclusions：我们认为，cytomegalic神经元，但不是气球细胞有可能是癫痫发生器，虽然可能不是煽动者，在严重的CD组织。
Purpose: Severe cortical dysplasia (CD) is characterized by the presence of cytomegalic neurons and balloon cells. These aberrant cells could participate in the generation of epileptic activity. The aim of this study was to morphologically and electrophysiologically characterize cells in pediatric CD tissue.Methods: We used infrared video-microscopy to visualize normal and abnormal-appearing cells. To characterize electrophysiological properties, we used whole-cell patch clamp recordings in tissue slices obtained from 42 cases of pediatric CD (ages 0.2-14 years). The pipette contained biocytin for determination of morphological features.Results: Approximately 25% of recorded cells displayed morphologic differences compared with normal-appearing pyramidal neurons, and were divided as follows: immature, misoriented, dysmorphic, cytomegalic, and balloon cells. Immature cells displayed electrophysiological membrane properties typi-cal of developing neurons. Misoriented pyramidal neurons and pyramidal neurons with dysmorphic processes displayed properties similar to normal-appearing pyramidal neurons. In contrast, cytomegalic neurons and balloon cells displayed abnormal membrane properties. Balloon cells had a very high input resistance and lacked voltage-gated Na+ and Ca2+ currents. Cytomegatic neurons had a very high membrane capacitance, very low input resistance, and showed signs of hyperexcitability, as exemplified spikes by the occurrence of repetitive, slowly inactivating Ca2+ when depolarized.Conclusions: We suggest that cytomegalic neurons but not balloon cells have the potential to be epileptic generators, although probably not instigators, in severe CD tissue.