Independent tonotopy and thalamocortical projection patterns in two adjacent parts of the classical primary auditory cortex in mice.
Independent tonotopy and thalamocortical projection patterns in two adjacent parts of the classical primary auditory cortex in mice.
复制标题
小鼠经典初级听觉皮层两个相邻部分的独立音调和丘脑皮质投射模式。
DOI：
10.1016/j.neulet.2016.11.062
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发表时间：
2017
期刊：
影响因子：
2.5
通讯作者：
Shibuki K
中科院分区：
文献类型：
--
作者：
2.Tsukano H;Horie M;Takahashi K;Hishida R;Takebayashi H;Shibuki K
在最近的修订划定的小鼠听觉皮层地图，尾听觉领域，最初被定义为初级听觉皮层（AI），分为AI和背内侧场（DM），基于不同的高频区。一个低频率区域以前没有建立在DM，因为在这个区域对低频音调的反应很弱。这可能导致DM是缺乏低频带的非典型区域的误解。在目前的研究中，我们证实DM有一个完全独立于AI的低频区。首先，我们进行了黄素蛋白荧光成像与改善的信号噪声比，并揭示了两个分离的低频区的存在下，在AI和DM。接下来，我们沿着AI或DM的tonotopic轴注射逆行神经示踪剂，以揭示内侧膝状体（MGv）腹侧部的丘脑起源。我们发现，投射到AI和DM的低频区的神经元在MGv内占据不同的位置，并且由投射到AI或DM的丘脑神经元组成的相互独立的地形组织。这些结果表明，AI和DM具有不同的低频区，具有不同的来自MGv的丘脑投射。我们的研究结果再次证实，在小鼠听觉皮层中，AI和DM应该被视为独立的区域。
Amid recent amendment of delineation of a mouse auditory cortical map, a caudal auditory field, originally defined as the primary auditory cortex (AI), was divided into the AI and dorsomedial field (DM), based on distinct high frequency areas. A low frequency area was not previously established in the DM because responses to low frequency tones were weak in this area. This may lead to the misconception that the DM is an atypical region that lacks a low frequency band. In the current study, we confirmed that the DM has a low frequency area that is completely independent from the AI. First, we conducted flavoprotein fluorescence imaging with improved signal to noise ratio and revealed the presence of two separated low frequency areas in the AI and DM. Next, we injected a retrograde neural tracer along the tonotopic axis of the AI or DM to reveal the thalamic origins in the ventral division of the medial geniculate body (MGv). We found that neurons projecting to low frequency areas of the AI and DM occupied different locations within the MGv and mutually independent topographic organizations consisting of thalamic neurons projecting to the AI or DM. These results indicate that the AI and DM have distinct low frequency areas with distinct thalamic projections from the MGv. Our findings reaffirm that the AI and DM should be regarded as independent regions in the mouse auditory cortex.