CONNECTIONS OF THE DORSAL NUCLEUS OF THE LATERAL LEMNISCUS - AN INHIBITORY PARALLEL PATHWAY IN THE ASCENDING AUDITORY-SYSTEM
CONNECTIONS OF THE DORSAL NUCLEUS OF THE LATERAL LEMNISCUS - AN INHIBITORY PARALLEL PATHWAY IN THE ASCENDING AUDITORY-SYSTEM
复制标题
DOI：
10.1002/cne.902760204
复制
发表时间：
1988-10-08
影响因子：
2.5
通讯作者：
HENKEL, CK
中科院分区：
文献类型：
--
作者：
SHNEIDERMAN, A;OLIVER, DL;HENKEL, CK
本研究探讨了外侧丘系背核（DNLL）及其传入和传出联系。在Nissl染色的材料中，DNLL有三个部分：背侧、腹侧和外侧。虽然每个部分都包含具有类似尼氏模式的神经元，但可以通过细胞的大小，形状和方向来区分细分。外侧DNLL含有DNLL神经元和来自鞍突的细胞的混合物。采用顺行轴突运输技术观察DNLL的传入联系。双侧DNLL的输入来自耳蜗前腹核和外侧上级橄榄，而单侧输入由同侧内侧上级橄榄和对侧DNLL提供。输入似乎有一个tonotopic组织。DNLL的传入纤维形成水平带，这些水平带在内外侧和喙尾侧都是连续的。DNLL的所有部分并不共享相同的输入，并且在某些通路的标记中存在内侧到外侧的梯度。为了研究DNLL的传出联系，采用了逆行和顺行轴突运输技术。DNLL投射至下丘和对侧DNLL。这些投影的地形表明，具有相似色调组织的区域是相连的。在下丘，向中央核的投射最重，并延伸到相邻的背侧和尾侧皮质、吻极核和腹外侧核。DNLL的轴突沿着中央核的纤维树突层终止，在对侧呈带状，而在同侧丘则较弥散。DNLL的传入和传出连接构成了一条多突触通路，与其他上行通路平行，到达下丘。其他上行通路包括耳蜗核至下丘的直接通路和经上级橄榄复合体的间接通路。上行通路的讨论，以他们的关系，下丘的细分，其预测的偏侧性，和他们在中央核的带型。与下丘的兴奋通路不同，DNLL的神经元可能使用GABA作为神经递质。来自DNLL的轴突终止于下丘，作为可能具有独特抑制功能的带。因此，多突触，DNLL通路可以提供前馈抑制输入下丘，双边，和对侧DNLL。
This study examines the dorsal nucleus of the lateral lemniscus (DNLL)and its afferent and efferent connections. In Nissl-stained material, DNLL has three parts: dorsal, ventral and lateral. Although each part contains neurons with similar Nissl patterns, the subdivisions may be distinguished by the size, shape and orientation of the cells. The lateral DNLL contains a mixture of DNLL neurons and cells from the sagulum. Afferent connections of DNLL were investigated with anterograde axonal transport techniques. Bilateral inputs to DNLL arise from the anteroventral cochlear nucleus and lateral superior olive, while unilateral inputs are provided by the ipsilateral medial superior olive and the contralateral DNLL. The inputs appear to have a tonotopic organization. Afferent fibers to DNLL form horizontal bands that are continuous both mediolaterally and rostrocaudally. All parts of DNLL do not share the same inputs, and a medial-to-lateral gradient in the labeling of some pathways is evident. To study the efferent connections of DNLL, both retrograde and anterograde axonal transport techniques were used. The DNLL projects to the inferior colliculus and the contralateral DNLL. The topography of these projections suggests that areas of similar tonotopic organization are connected. In the inferior colliculus, the projection is heaviest to the central nucleus and extends to the adjacent dorsal and caudal cortex, the rostral pole nucleus, and the ventrolateral nucleus, Axons from DNLL terminate along the fibrodendritic laminae of the central nucleus as bands that are prominant on the contralateral side, whereas those on the ipsilateral colliculus are more diffuse. The afferent and efferent connections of DNLL constitute a multisynaptic pathway, parallel to the other ascending pathways to the inferior colliculus. The other ascending pathways include the direct pathways from the cochlear nucleus to the inferior colliculus and the indirect pathways via the superior olivary complex. Ascending pathways are discussed as to their relationship to the subdivisions of the inferior colliculus, the laterality of their projections, and their banding patterns in the central nucleus. In contrast to the excitatory pathways to the inferior colliculus, the neurons in DNLL may use GABA as a neurotransmitter. Axons from the DNLL terminate in the inferior colliculus as bands that could have a unique inhibitory function. Thus, the multisynaptic, DNLL pathway may provide feed-forward inhibitory inputs to the inferior colliculus, bilaterally, and to the contralateral DNLL.