TOPOGRAPHIC ORGANIZATION OF CONVERGENT PROJECTIONS TO THE THALAMUS FROM THE INFERIOR COLLICULUS AND SPINAL-CORD IN THE RAT
TOPOGRAPHIC ORGANIZATION OF CONVERGENT PROJECTIONS TO THE THALAMUS FROM THE INFERIOR COLLICULUS AND SPINAL-CORD IN THE RAT
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DOI：
10.1002/cne.902640110
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发表时间：
1987-10-01
影响因子：
2.5
通讯作者：
REIS, DJ
中科院分区：
文献类型：
--
作者：
LEDOUX, JE;RUGGIERO, DA;REIS, DJ
本研究的目的是确定大鼠丘脑区域接收来自声学和脊髓投射系统的会聚感觉输入。采用WGA-HRP作为顺行轴突示踪剂，观察下丘和脊髓向丘脑传入神经的地形分布。在下丘注射后，在内侧膝状体（MGB）的腹侧、内侧和背侧分区以及丘脑后部的邻近区域，包括后界限核、后板间核、边缘区、针束周围区、束旁核的外侧或细胞旁部分，以及后界限核和扣上核之间的区域，都出现了终末标记。在丘脑尾侧，脊髓投射仍在网状结构中，位于丘顶终末场内侧。然而，在中位肌的中间水平，脊髓投影开始与collcollar field重叠，终止于中位肌的内侧分支、后板间核、边缘区、外侧束旁核以及锁骨上核和后界限核之间的区域。更重要的是，收敛区扩展到包括背侧MG区。因此，从下丘和脊髓到丘脑的传入投射在尾侧平面的交汇程度是分级的，最大的重叠发生在MGB的吻侧三分之一的水平。这些观察结果确定了声学和体觉整合的潜在区域，并可能解释了丘脑对声学和体觉输入配对的神经元可塑性的观察结果。
The purpose of this study was to identify thalamic areas receiving convergent sensory inputs from acoustic and spinal projection systems in the rat. The topographic distribution of afferents to the thalamus from the inferior colliculus and spinal cord was examined by using WGA-HRP as an anterograde axonal tracer. Following injections in the inferior colliculus, terminal labeling was present in ventral, medial, and dorsal divisions of the medial geniculate body (MGB) and in adjacent areas of the posterior thalamus, including the posterior limitans nucleus, the posterior intralaminar nucleus, the marginal zone, the peripeduncular region, the lateral or parvicellular part of the subparafascicular nucleus, and a region intercalated between the posterior limitans nucleus and the suprageniculate nucleus. In the caudal thalamus spinal projections remained in the reticular formation medial to the collicular terminal field. At intermediate levels of the MG, however, the spinal projection began to overlap the collicular field, terminating in the medial division of the MG and in the posterior intralaminar nucleus, the marginal zone, the lateral subparafascicular nucleus, and the area between the suprageniculate and posterior limitans nuclei. More rostrally, the convergent field expanded to include aspects of the dorsal MG division. The extent to which afferent projections to the thalamus from the inferior colliculus and spinal cord converge is thus graded in the caudorostral plane, with the greatest overlap occurring at the level of the rostral third of the MGB. These observations identify potential areas of acoustic and somesthetic integration and may account for observations of neuronal plasticity in the thalamus in response to the pairing of acoustic and somesthetic inputs.