Molecular mechanisms underlying inactivation of voltage-

本实验室利用了一项关于细胞内pH值对鱿鱼巨轴突膜兴奋性影响的新发现。在一定条件下，这些制剂要么以有节奏的、自发的方式激发动作电位，要么是静止的，即它们是双稳态的。我们在这些轴突中注入了计算机生成的噪声，以研究两种稳定状态之间的转换。膜噪声是中枢神经系统神经元，尤其是大脑神经元普遍存在的特征。双稳定性已经被假设发生在经历癫痫发作的大脑区域的神经元中。在其中一个细胞的自发放电周期的临界点上施加短时间电流脉冲可以终止其活动，也就是说，它可以使神经元复位到其稳定的休息状态。膜噪声可能是实现这一结果的一种更有效的方法，因为小幅度的噪声信号就足够了，并且噪声脉冲的定时不像电流脉冲那样关键。这些结果可能与设计植入大脑的装置作为控制癫痫发作活动的一种方式有关。

This laboratory has made use of a novel finding concerning the effects of intracellular pH on membrane excitability in squid giant axons. Under certain conditions these preparations either fire action potentials in a rhythmic, spontaneous manner, or they are quiescent, i.e., they are bistable. We have injected computer generated noise in these axons to investigate the transitions between the two stable states. Membrane noise is a ubiquitous feature of neurons in the central nervous system, especially neurons in the brain. Bistability has been hypothesized to occur in neurons in areas of the brain undergoing epiliptic seizures. Brief duration current pulses applied at a critical point in the spontaneous firing cycle of one of these cells can terminate the activity, that is, it can reset the neuron to its stable rest state. Membrane noise may be a more efficacious way of accomplishing this result, since a small amplitude noise signal is sufficient, and the timing of the noise pulse is not as critical as in the case of a current pulse. These results might have relevance in the design of implantable devices in the brain as one way of controlling seizure activity.