Morphological Characterization of Bushy Cells and Their Inputs in the Laboratory Mouse (Mus musculus) Anteroventral Cochlear Nucleus
Morphological Characterization of Bushy Cells and Their Inputs in the Laboratory Mouse (Mus musculus) Anteroventral Cochlear Nucleus
复制标题
DOI：
10.1371/journal.pone.0073308
复制
发表时间：
2013-08-26
期刊：
影响因子：
3.7
通讯作者：
Ryugo, David K.
中科院分区：
文献类型：
--
作者：
Lauer, Amanda M.;Connelly, Catherine J.;Ryugo, David K.
AVCN 的球形和球状浓密细胞接收巨大的听觉神经末梢，专门用于响应声音事件的高保真神经传输。最近对小鼠和其他啮齿类动物的研究表明，浓密细胞亚型之间的区别并不总是那么简单。我们对小鼠头尾轴的浓密细胞进行了系统研究，以了解引起小鼠报告的反应特性的形态变化。我们结合定量光学和电子显微镜来研究细胞形态、免疫染色以及沿头尾轴的初级和非初级突触输入的分布的变化。总体而言，没有发现浓密细胞特征存在较大的区域差异；然而，与尾部丛状细胞相比，喙部丛状细胞接受了不同的轴体输入补充。尾侧 AVCN 中初级听觉神经末梢的比例较大，而头侧 AVCN 中非初级兴奋性和抑制性输入更常见。头侧和尾侧 AVCN 初级听神经输入的其他超微结构特征相似。轴体听神经末梢的横截面积、突触后密度长度和曲率以及线粒体体积分数相似，尽管头侧听神经末梢在突触后密度附近含有更高浓度的突触小泡。这些数据证明了小鼠浓密细胞输入的突触组织存在区域差异，而不是细胞本身的形态特征。
Spherical and globular bushy cells of the AVCN receive huge auditory nerve endings specialized for high fidelity neural transmission in response to acoustic events. Recent studies in mice and other rodent species suggest that the distinction between bushy cell subtypes is not always straightforward. We conducted a systematic investigation of mouse bushy cells along the rostral-caudal axis in an effort to understand the morphological variation that gives rise to reported response properties in mice. We combined quantitative light and electron microscopy to investigate variations in cell morphology, immunostaining, and the distribution of primary and non-primary synaptic inputs along the rostral-caudal axis. Overall, large regional differences in bushy cell characteristics were not found; however, rostral bushy cells received a different complement of axosomatic input compared to caudal bushy cells. The percentage of primary auditory nerve terminals was larger in caudal AVCN, whereas non-primary excitatory and inhibitory inputs were more common in rostral AVCN. Other ultrastructural characteristics of primary auditory nerve inputs were similar across the rostral and caudal AVCN. Cross sectional area, postsynaptic density length and curvature, and mitochondrial volume fraction were similar for axosomatic auditory nerve terminals, although rostral auditory nerve terminals contained a greater concentration of synaptic vesicles near the postsynaptic densities. These data demonstrate regional differences in synaptic organization of inputs to mouse bushy cells rather than the morphological characteristic of the cells themselves.