Department of Biology, Neurosciences Institute, The University of Texas at San Antonio, San Antonio, TX, United States.
Front Neural Circuits. 2020 Jul 23;14:45. doi: 10.3389/fncir.2020.00045. eCollection 2020.
Previous studies have shown that cortico-striatal pathways link auditory signals to action-selection and reward-learning behavior through excitatory projections. Only recently it has been demonstrated that long-range GABAergic cortico-striatal somatostatin-expressing neurons in the auditory cortex project to the dorsal striatum, and functionally inhibit the main projecting neuronal population, the spiny projecting neuron. Here we tested the hypothesis that parvalbumin-expressing neurons of the auditory cortex can also send long-range projections to the auditory striatum. To address this fundamental question, we took advantage of viral and non-viral anatomical tracing approaches to identify cortico-striatal parvalbumin neurons (). Here, we describe their anatomical distribution in the auditory cortex and determine the anatomical and electrophysiological properties of layer 5 CS-Parv neurons. We also analyzed their characteristic voltage-dependent membrane potential gamma oscillation, showing that intrinsic membrane mechanisms generate them. The inherent membrane mechanisms can also trigger intermittent and irregular bursts (stuttering) of the action potential in response to steps of depolarizing current pulses.
先前的研究表明，皮质纹状体通路通过兴奋性投射将听觉信号与动作选择和奖励学习行为联系起来。直到最近才证明，听觉皮层中的长程 GABA 能皮质纹状体生长抑素表达神经元投射到背侧纹状体，并对主要投射神经元群，即棘投射神经元，发挥功能抑制作用。在这里，我们检验了这样一个假设，即听觉皮层中的钙结合蛋白表达神经元也可以向听觉纹状体发送长程投射。为了解决这个基本问题，我们利用病毒和非病毒解剖追踪方法来识别皮质纹状体钙结合蛋白神经元（）。在这里，我们描述了它们在听觉皮层中的解剖分布，并确定了第 5 层 CS-Parv 神经元的解剖和电生理特性。我们还分析了它们特征性的电压依赖性膜电位伽马振荡，表明内在的膜机制产生了它们。内在的膜机制也可以触发动作电位的间歇性和不规则爆发（口吃），以响应去极化电流脉冲的步骤。
