Fine Control of Sound Frequency Tuning and Frequency Discrimination Acuity by Synaptic Zinc Signaling in Mouse Auditory Cortex
Fine Control of Sound Frequency Tuning and Frequency Discrimination Acuity by Synaptic Zinc Signaling in Mouse Auditory Cortex
复制标题
DOI：
10.1523/jneurosci.1339-18.2018
复制
发表时间：
2019-01-30
影响因子：
5.3
通讯作者：
Anderson, Charles T.
中科院分区：
文献类型：
--
作者：
Kumar, Manoj;Xiong, Shanshan;Anderson, Charles T.
听觉皮层中的神经元被调谐到特定的声音频率范围。尽管神经元声音频率选择性的细胞和网络机制已经得到了很好的研究，反映了丘脑皮质和皮质内兴奋输入的相互作用，并通过皮质抑制进一步完善，但精确的突触信号传导机制仍然知之甚少。为了进一步了解这些机制及其对声音驱动行为的影响，我们在清醒和行为的雌性和雄性小鼠中使用了体内成像和行为方法。我们发现突触锌是一种神经传递和声音反应的调节剂，它使初级听觉皮层2/3层表达生长抑素的抑制神经元的声音频率调节变宽，使主要和小蛋白表达神经元的声音频率调节变尖。在缺乏皮质突触锌的情况下，小鼠检测声音频率变化的敏锐度降低。总之，我们的研究结果表明，锌对细胞类型的特异性作用有助于皮质声音频率调节并增强声音频率识别的敏锐度。
Neurons in the auditory cortex are tuned to specific ranges of sound frequencies. Although the cellular and network mechanisms underlying neuronal sound frequency selectivity are well studied and reflect the interplay of thalamocortical and intracortical excitatory inputs and further refinement by cortical inhibition, the precise synaptic signaling mechanisms remain less understood. To gain further understanding on these mechanisms and their effects on sound-driven behavior, we used in vivo imaging as well as behavioral approaches in awake and behaving female and male mice. We discovered that synaptic zinc, a modulator of neurotransmission and responsiveness to sound, sharpened the sound frequency tuning of principal and parvalbumin-expressing neurons and widened the sound frequency tuning of somatostatin-expressing inhibitory neurons in layer 2/3 of the primary auditory cortex. In the absence of cortical synaptic zinc, mice exhibited reduced acuity for detecting changes in sound frequencies. Together, our results reveal that cell-type-specific effects of zinc contribute to cortical sound frequency tuning and enhance acuity for sound frequency discrimination.