Electrophysiological properties of inferior olive neurons: A compartmental model.
Electrophysiological properties of inferior olive neurons: A compartmental model.
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下橄榄神经元的电生理特性：房室模型。
DOI：
10.1152/jn.1999.82.2.804
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发表时间：
1999
影响因子：
2.5
通讯作者：
M. Kawato
中科院分区：
文献类型：
--
作者：
N. Schweighofer;K. Doya;M. Kawato
作为探索下橄榄功能的一步，我们构建了橄榄神经元的生物物理模型，以检测其独特的电生理特性。该模型由两个隔室组成，以表示跨细胞膜的离子电流的已知分布，以及缝隙连接和突触输入的树突位置。体室包括低阈值钙电流(I(Ca_L))、异常内向整流电流(I(H))、钠电流(I(Na))和延迟整流钾电流(I(K_DR))。树突室含有高阈值钙电流(I(Ca_H))、钙依赖性钾电流(I(K_Ca))和通过电耦合流入其他细胞的电流(I(C))。首先，根据先前报道的实验数据设置了这些电流的动力学参数。接下来，确定剩余的自由参数来解释单个橄榄核神经元在体外的静态和尖峰特性。然后，我们使用分支分析和广泛的双参数搜索进行了一系列模拟药理学实验。与前人的研究一致，我们定量地证明了钙L在放电兴奋性中的主要作用。此外，正如Bal和McCormick先前提出的那样，i(H)在尖峰的产生和振荡的周期中起着重要的调节作用。最后，我们研究了电耦合在两个耦合的尖峰细胞中的作用。根据耦合强度、超极化水平以及I(Ca_L)和I(H)调制的不同，耦合的细胞有四种不同的同步模式：细胞可以是同相、相移或反相的，也可以呈现复杂的去同步尖峰模式。因此，这些模拟结果支持了违反直觉的假设，即电耦合可以使结合的下层橄榄细胞失去同步化。
As a step in exploring the functions of the inferior olive, we constructed a biophysical model of the olivary neurons to examine their unique electrophysiological properties. The model consists of two compartments to represent the known distribution of ionic currents across the cell membrane, as well as the dendritic location of the gap junctions and synaptic inputs. The somatic compartment includes a low-threshold calcium current (I(Ca_l)), an anomalous inward rectifier current (I(h)), a sodium current (I(Na)), and a delayed rectifier potassium current (I(K_dr)). The dendritic compartment contains a high-threshold calcium current (I(Ca_h)), a calcium-dependent potassium current (I(K_Ca)), and a current flowing into other cells through electrical coupling (I(c)). First, kinetic parameters for these currents were set according to previously reported experimental data. Next, the remaining free parameters were determined to account for both static and spiking properties of single olivary neurons in vitro. We then performed a series of simulated pharmacological experiments using bifurcation analysis and extensive two-parameter searches. Consistent with previous studies, we quantitatively demonstrated the major role of I(Ca_l) in spiking excitability. In addition, I(h) had an important modulatory role in the spike generation and period of oscillations, as previously suggested by Bal and McCormick. Finally, we investigated the role of electrical coupling in two coupled spiking cells. Depending on the coupling strength, the hyperpolarization level, and the I(Ca_l) and I(h) modulation, the coupled cells had four different synchronization modes: the cells could be in-phase, phase-shifted, or anti-phase or could exhibit a complex desynchronized spiking mode. Hence these simulation results support the counterintuitive hypothesis that electrical coupling can desynchronize coupled inferior olive cells.
影响因子：
2.5
作者：
HUGUENARD, JR;MCCORMICK, DA
通讯作者：
MCCORMICK, DA
影响因子：
2.5
作者：
R. Traub;R. Wong;R. Miles;H. Michelson
通讯作者：
R. Traub;R. Wong;R. Miles;H. Michelson