Influences of membrane properties on phase response curve and synchronization stability in a model globus pallidus neuron
Influences of membrane properties on phase response curve and synchronization stability in a model globus pallidus neuron
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DOI：
10.1007/s10827-011-0368-2
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发表时间：
2012-06-01
影响因子：
1.2
通讯作者：
Kitano, Katsunori
中科院分区：
文献类型：
--
作者：
Fujita, Tomohiro;Fukai, Tomoki;Kitano, Katsunori
苍白球（GPe）和丘脑底核（Subthalamic nucleus，Nucleus）的活动模式与基底神经节的运动功能和功能障碍密切相关。在由多巴胺耗竭引起的病理状态下，STN-GPe网络表现出节律性同步活动，伴随着突触中的反弹爆发。因此，研究基底神经节的活动转换机制是理解基底神经节功能的关键。由于GPe神经元的同步化可以引起病理性的突触反弹爆发，因此研究GPe神经元的同步化是非常重要的。为了澄清这个问题，我们应用相位还原技术的电导为基础的GPe神经元模型，以获得的相位响应曲线（PRC）和耦合GPe神经元之间的相互作用函数。使用PRC和相互作用函数，我们研究了GPe网络的稳态活性如何取决于膜的固有性质，膜上的不同离子电导。我们注意到持续性钠电流、快速延迟整流Kv 3钾电流、M型钾电流和小电导钙依赖性钾电流的变化影响PRC的形状和稳态。这些电流对PRC形状的影响可归因于动作电位后即刻的放电期延长和相位响应减少。特别是，由M型钾和SK电流引起的慢钾电流是导致相位响应降低的原因。这些结果表明，膜的性质调制控制同步化/在GPe和STN-GPe活动的病理模式。
The activity patterns of the globus pallidus (GPe) and subthalamic nucleus (STN) are closely associated with motor function and dysfunction in the basal ganglia. In the pathological state caused by dopamine depletion, the STN-GPe network exhibits rhythmic synchronous activity accompanied by rebound bursts in the STN. Therefore, the mechanism of activity transition is a key to understand basal ganglia functions. As synchronization in GPe neurons could induce pathological STN rebound bursts, it is important to study how synchrony is generated in the GPe. To clarify this issue, we applied the phase-reduction technique to a conductance-based GPe neuronal model in order to derive the phase response curve (PRC) and interaction function between coupled GPe neurons. Using the PRC and interaction function, we studied how the steady-state activity of the GPe network depends on intrinsic membrane properties, varying ionic conductances on the membrane. We noted that a change in persistent sodium current, fast delayed rectifier Kv3 potassium current, M-type potassium current and small conductance calcium-dependent potassium current influenced the PRC shape and the steady state. The effect of those currents on the PRC shape could be attributed to extension of the firing period and reduction of the phase response immediately after an action potential. In particular, the slow potassium current arising from the M-type potassium and the SK current was responsible for the reduction of the phase response. These results suggest that the membrane property modulation controls synchronization/asynchronization in the GPe and the pathological pattern of STN-GPe activity.