Proportion of N-type calcium current activated by action potential stimuli.
Proportion of N-type calcium current activated by action potential stimuli.
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动作电位刺激激活的 N 型钙电流的比例。
DOI：
10.1152/jn.01289.2004
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Meriney,StephenD
中科院分区：
文献类型：
--
作者：
KingJr,JDarwin;Meriney,StephenD
N型钙电流在许多神经元功能中是重要的，包括细胞信号传导、基因表达的调节和神经递质释放的触发。通常，这些不同的细胞功能的控制是由钙进入亚细胞区室的空间和时间模式。这个问题的根本是动作电位在触发钙通道开放方面的有效性。以鸡睫状神经节神经元为模型细胞，研究动作电位去极化过程中N型钙电流的激活。记录了几种不同的动作电位形状，用作电压命令模板，并进行改变，以便控制动作电位诱发的电流可以与拓宽的动作电位命令引起的电流进行比较。根据用于激活鸡睫状神经节神经元中钙电流的动作电位形状，以及进行记录时的温度，可以激活不同比例（I/Imax）的N型钙电流。测量的最大比例发生在37°C下使用宽睫状神经节细胞索马动作电位激活钙电流时（100%）。测量的最小比例发生在使用快速、高温调节的青蛙运动神经元神经末梢动作电位在室温下激活钙电流（10%）。这些数据进行了讨论相对于对细胞信号和调节发射器释放的影响。
N-type calcium currents are important in many neuronal functions, including cellular signaling, regulation of gene expression, and triggering of neurotransmitter release. Often the control of these diverse cellular functions is governed by the spatial and temporal patterns of calcium entry in subcellular compartments. Underlying this issue is the effectiveness of action potentials at triggering calcium channel opening. Chick ciliary ganglion neurons were used as model cells to study the activation of N-type calcium current during action potential depolarization. Several different action potential shapes were recorded, used as voltage command templates, and altered such that control action potential–evoked currents could be compared with those elicited by broadened action potential commands. Depending on the action potential shape used to activate calcium currents in chick ciliary ganglion neurons, and the temperature at which recordings were performed, varying proportions (I/Imax) of N-type calcium current could be activated. The largest proportion measured occurred using a broad ciliary ganglion cell soma action potential to activate calcium current at 37°C (100%). The smallest proportion measured occurred using a fast, high-temperature–adjusted frog motoneuron nerve terminal action potential to activate calcium current at room temperature (10%). These data are discussed with respect to the impact on cellular signaling and the regulation of transmitter release.