LOCALIZATION AND MOBILITY OF OMEGA-CONOTOXIN SENSITIVE CA-2+ CHANNELS IN HIPPOCAMPAL CA1 NEURONS
LOCALIZATION AND MOBILITY OF OMEGA-CONOTOXIN SENSITIVE CA-2+ CHANNELS IN HIPPOCAMPAL CA1 NEURONS
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DOI：
10.1126/science.2543080
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发表时间：
1989-06-09
期刊：
影响因子：
56.9
通讯作者：
ANGELIDES, KJ
中科院分区：
文献类型：
--
作者：
JONES, OT;KUNZE, DL;ANGELIDES, KJ
电压依赖性Ca2+通道（VDCCs）是突触可塑性、振荡行为和大脑区域（如海马）节律性放电的调节剂。利用选择性探针- omega的生物活性荧光和生物素化衍生物测定了CA1海马神经元上VDCCs的分布和横向迁移。- concontoxin与圆形双胞法、数字荧光成像和光漂白回收显微镜相结合。在非神经支配的细胞体上，vdcs呈多簇组织，而在神经支配后，vdcs集中并固定在突触接触部位。在树突上，VDCC分布呈点状，被广泛的裸区中断或突然终止。荧光漂白法发现85%以上的树突状VDCCs是不动的。因此，在突触接触之前，特定的机制将vdcs定位、分离并固定在神经元细胞体和特定的树突位点上。这种分布的调节可能是决定海马CA1神经元放电活动和整合特性的关键。
Voltage-dependent Ca2+ channels (VDCCs) are modulators of synaptic plasticity, oscillatory behavior, and rhythmic firing in brain regions such as the hippocampus. The distribution and lateral mobility of VDCCs ON CA1 hippocampal neurons have been determined with biologically active fluorescent and biotinylated derivatives of the selective probe .omega.-conotoxin in conjunction with circular ditynadallism, digital fluorescence imaging, and photobleach recovery microscopy. On noninnervated cell bodies, VDCCs were found ot be organized in multiple clusters, whereas after innervation the VDCCs were concentrated and immobilized at synaptic contact sites. On dendrites, VDCC distribution was punctate and was interrupted by extensive bare regions or abruptly terminated. More than 85% of the dendritic VDCCs were found to be immobile by fluorescence photobleach recovery. Thus, before synaptic contact, specific mechanisms target, segregate, and immobilize VDCCs to neuronal cell bodies and to specialized dendritic sites. Regulation of this distribution may be critical in determining the firing activity and integrative properties of hippocampal CA1 neurons.