An arithmetic rule for shunting inhibition in pyramidal neurons

• 作 者: Xu-DongWANG;JiangHAO;Mu-MingPOO;Xiao-HuiZHANG;
• 机 构: Institute of Neuroscience, Chinese Academy of Sciences, Shanghai 200031, China
• 出 处: 中国神经科学学会第四次会员代表大会暨第七届全国学术会议(The 7th Biennial Meeting and the
• 发表日期: 2007年期

　　The shunting effect of the inhibitory input (Ⅰ) on the depolarization triggered by the excitatory input (E) plays a major role in dendritic integration.We here report a simple nonlinear shunting subtraction rule (SSR) that accurately predicts experimentally observed dendrite location-specific shunting inhibition.This rule was derived from realistic modeling of a reconstructed hippocampal CA1 pyramidal neuron and its predictions were verified by measurements of the summation of glutamate-and GABA-induced potentials in rat hippocampal slices.We found a striking asymmetry in the dependence of shunting inhibition on E/I location,as reflected by a single parameter k in SSR:For a given Ⅰ on the dendritic trunk,k decays rapidly with increasing E-I distance for more proximal E,but remains largely uniform for more distal E.This asymmetry in k is determined largely by the cable property and can be modulated by active conductances.For Ⅰ on the oblique branch,shunting inhibition is largely restricted within the branch,with the same asymmetry in shunting proximal vs.distal E.SSR provides a simple arithmetic rule for incorporating dendrite-location specific E-I integration into computational analysis of signal processing in single neurons and neural networks.