Kaczmarek Leonard K, Bhattacharjee Arin, Desai Rooma, Gan Li, Song Ping, von Hehn Christian A A, Whim Matthew D, Yang Bo
Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
Hear Res. 2005 Aug;206(1-2):133-45. doi: 10.1016/j.heares.2004.11.023.
The firing patterns of neurons in central auditory pathways encode specific features of sound stimuli, such as frequency, intensity and localization in space. The generation of the appropriate pattern depends, to a major extent, on the properties of the voltage-dependent potassium channels in these neurons. The mammalian auditory pathways that compute the direction of a sound source are located in the brainstem and include the connection from bushy cells in the anteroventral cochlear nucleus (AVCN) to the principal neurons of the medial nucleus of the trapezoid body (MNTB). To preserve the fidelity of timing of action potentials that is required for sound localization, these neurons express several types of potassium channels, including the Kv3 and Kv1 families of voltage-dependent channels and the Slick and Slack sodium-dependent channels. These channels determine the pattern of action potentials and the amount of neurotransmitter released during repeated stimulation. The amplitude of currents carried by one of these channels, the Kv3.1b channel, is regulated in the short term by protein phosphorylation, and in the long term, by changes in gene expression, such that the intrinsic excitability of the neurons is constantly being regulated by the ambient auditory environment.
中枢听觉通路中神经元的放电模式编码声音刺激的特定特征，如频率、强度和空间定位。适当模式的产生在很大程度上取决于这些神经元中电压依赖性钾通道的特性。计算声源方向的哺乳动物听觉通路位于脑干，包括从前庭蜗神经核（AVCN）的浓密细胞到梯形体内侧核（MNTB）的主要神经元的连接。为了保持声音定位所需的动作电位时间的保真度，这些神经元表达几种类型的钾通道，包括电压依赖性通道的Kv3和Kv1家族以及Slick和Slack钠依赖性通道。这些通道决定动作电位的模式以及重复刺激期间释放的神经递质的量。这些通道之一Kv3.1b通道所携带电流的幅度在短期内受蛋白质磷酸化调节，长期受基因表达变化调节，从而使神经元的内在兴奋性不断受到周围听觉环境的调节。
