神经元胞体-树突的耦合对放电模式影响的仿真研究

A Simulation Study of Relationship between Coupling Effect of Soma-Dendrite and Firing Patterns

应用神经元胞体-树突放电模型,在胞体与树突不同耦合作用的情况下,研究神经元放电模式的变化。设计三类刺激:胞体输入刺激(A)、树突输入刺激(B)、对胞体和树突同时输入刺激(A+B),分别研究在不同耦合电导gc时神经元的放电模式,通过在刺激(A+B)与刺激A和B时放电模式比较,研究输入刺激和放电模式的非线性关系。结果表明:(1)当耦合电导gc=0mS/cm2时,胞体和树突为相互独立的两个房室;(2)当耦合电导gc→∞时,胞体和树突合并为一个房室。在以上两类情况下,对两个房室输入(A+B)时胞体的放电与分别A和B叠加时的放电呈线性关系。(3)当耦合电导0<gc<∞时,胞体的放电模式随耦合电导的变化呈现节律性放电→爆发性放电→节律性放电的复杂变化。在0<gc<∞mS/cm2时,输入(A+B)时胞体的放电模式与输入呈现非线性关系。综上,胞体-树突之间的耦合对神经元放电模式具有影响作用。

The aim of this study is to investigate how firing patterns of hippocampus neuron change with coupling effect between soma and dendrite via simulation of single neuron firings by soma-dendrite model. The model was given stimulations to soma only （A）, to dendrite only （B）, to both soma and dendrite （A ＋ B）. Results showed： （1） When gc = 0mS/cm^2, soma and dendrite were two independent unit; （2） When gc→∞, the model was reduced to single compartment model. Under these two extremes, firing patterns of both compartments under （A ＋ B） was linear to that of the sum of A and B. （3） When gc was 0 〈 gc 〈 ∞ mS/cm^2, firing patterns of both compartments changed in a complicated manner with gc from repetitive firing to bursting and again repetitive firing. Firing patterns of both compartments for gc in this range under （ A ＋ B） was nonlinear to that of the sum of A and B.