Potassium Channels and Dendritic Function in Hippocampa*

不均匀密度的亚阈值，快速失活的钾通道调节信号在海马区CA1锥体神经元树突中的传播。这种不均匀的分布(在树突中的表达高于在胞体中的表达)意味着树突的电学性质与胞体的电学性质明显不同。传入的突触信号是由这些通道的活动形成的，一旦在轴突中启动，动作电位在传播回树突时逐渐降低幅度。通过结合海马脑片的膜片钳记录和分子生物学技术，分子神经生理学和生物物理学单位研究了CA1树突表达的电压门控通道的电生理特性和分子性质，它们的表达是如何调控的，以及它们在突触整合和可塑性中的作用。

A nonuniform density of subthreshold, rapidly inactivating potassium channels regulates signal propagation in the dendrites of CA1 pyramidal neurons of the hippocampus. This nonuniform distribution (with higher expression in the dendrites than in the soma) means that the electrical properties of the dendrites are markedly different from those of the soma. Incoming synaptic signals are shaped by the activity of these channels, and action potentials, once initiated in the axon, progressively decrease in amplitude as they propagate back into the dendrites. By combining patch clamp recording in brain slices of the hippocampus with molecular biology techniques, the Molecular Neurophysiology and Biophysics Unit investigates the electrophysiological properties and molecular nature of the voltage-gated channels expressed in CA1 dendrites, how their expression is regulated, and their role in synaptic integration and plasticity.