ACTIVE PROPAGATION OF SOMATIC ACTION-POTENTIALS INTO NEOCORTICAL PYRAMIDAL CELL DENDRITES
ACTIVE PROPAGATION OF SOMATIC ACTION-POTENTIALS INTO NEOCORTICAL PYRAMIDAL CELL DENDRITES
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DOI：
10.1038/367069a0
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发表时间：
1994-01-06
期刊：
影响因子：
64.8
通讯作者：
SAKMANN, B
中科院分区：
文献类型：
--
作者：
STUART, GJ;SAKMANN, B
哺乳动物中枢神经系统的神经元树突被认为是一种电被动结构，它将突触电位输送到体和轴突初始段，即动作电位起始的位置1,2。然而，最近的研究表明，许多神经元的树突不是被动的，而是包含主动电导3,4。这些树突电压激活通道在神经元动作电位启动中的作用在很大程度上是未知的。为了直接评估这一点，膜片钳记录了大脑切片中新皮质锥体细胞的树突。在树突全细胞记录过程中，电压激活的钠电流可通过去极化电流脉冲或突触刺激诱发动作电位。为了确定这些动作电位的起始位置，同时从同一细胞的体细胞和根尖树突或轴突进行全细胞记录。这些实验表明，动作电位首先在轴突启动，然后主动传播回树突树。
THE dendrites of neurons in the mammalian central nervous system have been considered as electrically passive structures which funnel synaptic potentials to the soma and axon initial segment, the site of action potential initiation1,2.More recent studies, however, have shown that the dendrites of many neurons are not passive, but contain active conductances3,4. The role of these dendritic voltage-activated channels in the initiation of action potentials in neurons is largely unknown. To assess this directly, patch-clamp recordings were made from the dendrites of neocortical pyramidal cells in brain slices. Voltage-activated sodium currents were observed in dendritic outside-out patches, while action potentials could be evoked by depolarizing current pulses or by synaptic stimulation during dendritic whole-cell recordings. To determine the site of initiation of these action potentials, simultaneous whole-cell recordings were made from the soma and the apical dendrite or axon of the same cell. These experiments showed that action potentials are initiated first in the axon and then actively propagate back into the dendritic tree.