Association of potassium channel Kv3.4 subunits with pre- and post-synaptic structures in brainstem and spinal cord
Association of potassium channel Kv3.4 subunits with pre- and post-synaptic structures in brainstem and spinal cord
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DOI：
10.1016/j.neuroscience.2004.03.051
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发表时间：
2004-01-01
期刊：
影响因子：
3.3
通讯作者：
Deuchars, J
中科院分区：
文献类型：
--
作者：
Brooke, RE;Atkinson, L;Deuchars, J
电压门控钾离子通道（Kv）分为8个亚家族（Kv 1 -8），在决定神经元兴奋性方面起主要作用。Kv 3亚家族的成员在CNS中高度丰富，每个Kv 3基因（Kv3.1-Kv3.4）表现出独特的表达模式，尽管单个神经元可以表达一种以上的亚型。Kv 3亚基中，Kv3.4亚基在神经系统中的分布相对较少，特别是在大鼠的脑干和脊髓中。我们进行免疫组织化学，以确定细胞和亚细胞分布的Kv3.4亚基在这些领域。Kv3.4亚单位免疫反应（Kv3.4-IR）广泛分布于中间外侧细胞柱（IML）、迷走神经背核（DVN）、疑核（NA）和孤束核（NTS）等多个区域，呈密集点状染色。在腹角突触前的位置被证实的共同定位Kv3.4-IR与突触囊泡蛋白，SV 2，也与谷氨酸囊泡标记囊泡谷氨酸转运蛋白（VGIuT）1，VGIuT 2或甘氨酸转运蛋白GlyT 2，这表明了兴奋性和抑制性神经传递的通道的作用。电镜证实Kv3.4-IR在VH、IML、DVN、NA和NTS的突触前终末定位。然而，有趣的是，Kv3.4-IR的补丁也揭示了突触后在整个这些地区的树突和体细胞结构。这种染色是惊人的，由于其定位在突触连接处的终端与兴奋功能的形态特征一致，这表明与突触后密度。因此，Kv3.4-IR的突触前和突触后定位表明在控制递质释放和调节神经元兴奋性中的作用。(C)2004年IBRO。由爱思唯尔有限公司出版。保留所有权利。
Voltage-gated K+ channels (Kv) are divided into eight subfamilies (Kv1-8) and play a major role in determining the excitability of neurones. Members of the Kv3 subfamily are highly abundant in the CNS, with each Kv3 gene (Kv3.1-Kv3.4) exhibiting a unique pattern of expression, although single neurones can express more than one subtype. Of the Kv3 subunits relatively little is known of the Kv3.4 subunit distribution in the nervous system, particularly in the brainstem and spinal cord of the rat. We performed immunohistochemistry to determine both the cellular and subcellular distribution of the Kv3.4 subunit in these areas. Kv3.4 subunit immunoreactivity (Kv3.4-IR) was widespread, with dense, punctate staining in many regions including the intermediolateral cell column (IML) and the dorsal vagal nucleus (DVN), nucleus ambiguus (NA) and nucleus tractus solitarius (NTS). In the ventral horn a presynaptic location was confirmed by co-localization of Kv3.4-IR with the synaptic vesicle protein, SV2 and also with the glutamate vesicle markers vesicular glutamate transporter (VGIuT) 1, VGIuT2 or the glycine transporter GlyT2, suggesting a role for the channel in both excitatory and inhibitory neurotransmission. Electron microscopy confirmed a presynaptic terminal location of Kv3.4-IR in the VH, IML, DVN, NA and NTS. Interestingly however, patches of Kv3.4-IR were also revealed postsynaptically in dendritic and somatic structures throughout these areas. This staining was striking due to its localization at synaptic junctions at terminals with morphological features consistent with excitatory functions, suggesting an association with the postsynaptic density. Therefore the pre and postsynaptic localization of Kv3.4-IR suggests a role both in the control of transmitter release and in regulating neuronal excitability. (C) 2004 IBRO. Published by Elsevier Ltd. All rights reserved.