Smilow Neuroscience Program, and Departments of Physiology and Neuroscience and Biochemistry, Smilow Research Center, New York University School of Medicine, New York, NY 10016, USA.
Neuroscientist. 2009 Dec;15(6):651-68. doi: 10.1177/1073858409341973.
Action potentials (APs) provide the primary means of rapid information transfer in the nervous system. Where exactly these signals are initiated in neurons has been a basic question in neurobiology and the subject of extensive study. Converging lines of evidence indicate that APs are initiated in a discrete and highly specialized portion of the axon-the axon initial segment (AIS). The authors review key aspects of the organization and function of the AIS and focus on recent work that has provided important insights into its electrical signaling properties. In addition to its main role in AP initiation, the new findings suggest that the AIS is also a site of complex AP modulation by specific types of ion channels localized to this axonal domain.
动作电位 (APs) 提供了神经系统中快速信息传递的主要手段。这些信号在神经元中的确切起始点一直是神经生物学中的一个基本问题，也是广泛研究的主题。越来越多的证据表明，APs 是在轴突的一个离散且高度特化的部分——轴突起始段 (AIS) 中发起的。作者回顾了 AIS 的组织和功能的关键方面，并重点介绍了最近的工作，这些工作为深入了解其电信号特性提供了重要的见解。除了在 AP 起始中的主要作用外，新的发现还表明，AIS 也是特定类型离子通道在该轴突区域定位的复杂 AP 调节的部位。
