Rose C R
Physiological Institute, University of Munich, Germany.
Neuroscientist. 2002 Dec;8(6):532-9. doi: 10.1177/1073858402238512.
A basic characteristic of animal cells is the maintenance of a steep inwardly directed electrochemical gradient for sodium ions. In vertebrate neurons, this Na+ gradient energizes intracellular ion regulation and enables influx of Na+ during action potentials and excitatory postsynaptic currents. Several studies suggested that Na+ ions could also play a role in activity-dependent synaptic plasticity. This review focuses on recent studies that demonstrated the presence of substantial intracellular Na+ transients during action potential firing or excitatory synaptic transmission in postsynaptic dendrites and dendritic spines. The large amplitudes of these activity-induced Na+ transients suggest that this signal will significantly alter electrical and biochemical properties of spines and dendrites and might influence the properties of synaptic transmission.
动物细胞的一个基本特征是维持钠离子向内的陡峭电化学梯度。在脊椎动物神经元中，这种钠离子梯度为细胞内离子调节提供能量，并在动作电位和兴奋性突触后电流期间使钠离子内流。多项研究表明，钠离子在依赖活动的突触可塑性中也可能发挥作用。本综述聚焦于近期的研究，这些研究表明在突触后树突和树突棘的动作电位发放或兴奋性突触传递过程中存在大量细胞内钠离子瞬变。这些由活动诱导的钠离子瞬变的大振幅表明，该信号将显著改变树突棘和树突的电学和生化特性，并可能影响突触传递的特性。
