PDF(Pubmed)
Abstract：
Parvalbumin-expressing (PV+) inhibitory interneurons drive gamma oscillations (30-80 Hz), which underlie higher cognitive functions. In this review, we discuss two groups/aspects of fundamental properties of PV+ interneurons. In the first group (dubbed Before Axon), we list properties representing optimal synaptic integration in PV+ interneurons designed to support fast oscillations. For example: [i] Information can neither enter nor leave the neocortex without the engagement of fast PV+ -mediated inhibition; [ii] Voltage responses in PV+ interneuron dendrites integrate linearly to reduce impact of the fluctuations in the afferent drive; and [iii] Reversed somatodendritic Rm gradient accelerates the time courses of synaptic potentials arriving at the soma. In the second group (dubbed After Axon), we list morphological and biophysical properties responsible for (a) short synaptic delays, and (b) efficient postsynaptic outcomes. For example: [i] Fast-spiking ability that allows PV+ interneurons to outpace other cortical neurons (pyramidal neurons). [ii] Myelinated axon (which is only found in the PV+ subclass of interneurons) to secure fast-spiking at the initial axon segment; and [iii] Inhibitory autapses - autoinhibition, which assures brief biphasic voltage transients and supports postinhibitory rebounds. Recent advent of scientific tools, such as viral strategies to target PV cells and the ability to monitor PV cells via in vivo imaging during behavior, will aid in defining the role of PV cells in the CNS. Given the link between PV+ interneurons and cognition, in the future, it would be useful to carry out physiological recordings in the PV+ cell type selectively and characterize if and how psychiatric and neurological diseases affect initiation and propagation of electrical signals in this cortical sub-circuit. Voltage imaging may allow fast recordings of electrical signals from many PV+ interneurons simultaneously.
摘要：
表达小白蛋白（PV）的抑制性中间神经元驱动伽马振荡（30-80Hz），这是更高的认知功能的基础。在这次审查中,我们讨论了PV中间神经元的基本特性的两组/方面。在第一组（称为轴突之前）中，我们列出了代表PV中间神经元中最佳突触整合的属性，旨在支持快速振荡。例如：[i]如果不参与快速PV介导的抑制，信息既不能进入也不能离开新皮质；[ii]PV中间神经元树突中的电压响应线性整合以减少传入驱动波动的影响；[iii]反向的体树突Rm梯度加速了突触电位到达体的时间进程。在第二组（称为轴突之后）中，我们列出了负责(a)短突触延迟的形态学和生物物理特性，和(b)有效的突触后结果。例如：[i]快速尖峰能力，允许PV中间神经元超过其他皮质神经元（锥体神经元）。[ii]有髓鞘的轴突（仅在中间神经元的PV子类中发现），以确保在初始轴突段的快速尖峰；和[iii]抑制性自适应-自抑制，这确保了短暂的双相电压瞬变并支持抑制后反弹。最近出现的科学工具，例如靶向PV细胞的病毒策略和通过体内行为成像监测PV细胞的能力，将有助于确定PV细胞在CNS中的作用。鉴于PV中间神经元和认知之间的联系，在未来,选择性地在PV+细胞类型中进行生理记录并表征精神病和神经系统疾病是否以及如何影响该皮质子电路中电信号的启动和传播将是有用的。电压成像可以允许同时快速记录来自许多PV+中间神经元的电信号。
