Ultrastructural localization of high-affinity choline transporter in the rat neuromuscular junction: Enrichment on synaptic vesicles
Ultrastructural localization of high-affinity choline transporter in the rat neuromuscular junction: Enrichment on synaptic vesicles
复制标题
DOI：
10.1002/syn.20029
复制
发表时间：
2004-07-01
期刊：
影响因子：
2.3
通讯作者：
Misawa, H
中科院分区：
文献类型：
--
作者：
Nakata, K;Okuda, T;Misawa, H
在胆碱能神经元中，Na+和Cl-依赖的、半胆碱敏感的高亲和力胆碱摄取系统被认为是乙酰胆碱（ACh）合成的限速步骤。该系统是高度调节的神经元活动，胆碱的摄取增加的条件下，乙酰胆碱释放是有利的。在这里，我们分析了超微结构定位的高亲和力胆碱转运蛋白（CHT）在大鼠神经肌肉接头与两个单独的抗体。大多数（>90%）的免疫金标记的CHT被观察到突触囊泡，而不是突触前质膜。不到5%的金银颗粒与质膜相关，超过70%的这种颗粒位于突触前活动区内或附近。我们的形态学数据支持最近的假设，CHT从突触囊泡到质膜的贩运耦合神经元活动和胆碱摄取。(C)2004 Wiley-Liss，Inc.
In cholinergic neurons, Na+- and Cl--dependent, hemicholinium-3-sensitive, high-affinity choline uptake system is thought to be the rate-limiting step in acetylcholine (ACh) synthesis. The system is highly regulated by neuronal activity; the choline uptake is increased by a condition in which ACh release is favored. Here we analyzed the ultrastructural localization of the high-affinity choline transporter (CHT) in the rat neuromuscular junctions with two separate antibodies. The majority (>90%) of immunogold labeling of CHT was observed on synaptic vesicles rather than the presynaptic plasma membrane. Less than 5% of the gold-silver particles were associated with the plasma membrane, and more than 70% of such particles were localized within or in close vicinity to presynaptic active zones. Our morphological data support the recent hypothesis that trafficking of CHT from synaptic vesicles to the plasma membrane couples neuronal activity and choline uptake. (C) 2004 Wiley-Liss, Inc.