We applied compartmental computer modeling to test a model of spike shape change in the jellyfish, Polyorchis penicillatus, to determine whether adaptive spike shortening can be attributed to the inactivation properties of a potassium channel. We modeled the jellyfish outer nerve-ring as a continuous linear segment, using ion channel and membrane properties derived in earlier studies. The model supported action potentials that shortened as they propagated away from the site of initiation and this was found to be largely independent of potassium channel inactivation. Spike broadening near the site of initiation was found to be due to a depolarization plateau that collapsed as two spikes spread from the point of initiation. The lifetime of this plateau was found to depend critically on the inward current flux and the space constant of the membrane. These data suggest that the spike shape changes may be due not only to potassium channel inactivation, but also to the passive properties of the membrane.

中文翻译：

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传播过程中电耦合网络中动作电位形状的变化：计算机模拟。

我们应用隔室计算机建模来测试水母 Polyorchis penicillatus 中尖峰形状变化的模型，以确定适应性尖峰缩短是否可归因于钾通道的失活特性。我们使用早期研究中得出的离子通道和膜特性将水母外神经环建模为一个连续的线性段。该模型支持动作电位随着它们从起始位点传播而缩短，并且发现这在很大程度上与钾通道失活无关。发现起始点附近的尖峰变宽是由于去极化平台随着两个尖峰从起始点扩散而坍塌。发现该平台的寿命主要取决于内向电流通量和膜的空间常数。