DESCENDING PATHWAYS FROM SUPERIOR COLLICULUS - AUTORADIOGRAPHIC ANALYSIS IN RHESUS-MONKEY (MACACA-MULATTA)
DESCENDING PATHWAYS FROM SUPERIOR COLLICULUS - AUTORADIOGRAPHIC ANALYSIS IN RHESUS-MONKEY (MACACA-MULATTA)
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DOI：
10.1002/cne.901730311
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发表时间：
1977-01-01
影响因子：
2.5
通讯作者：
HARTING, JK
中科院分区：
文献类型：
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作者：
HARTING, JK
采用放射自显像示踪方法对恒河猴（M. mulatta）的各种下行构造通路及其靶区进行了识别。大多数下行构造轴突起源于位于视层（第三层）腹侧的collcollae纹层。这些下行轴突可分为2个主要束或束，即同侧构造桥-构造球束和交叉构造脊髓束（或前背束）。除了这两条主要的通路，还有一条较小的，相接的突起。同侧通路向外侧和腹侧走行，终止于双侧旁核、中脑网状结构、桥脑背外侧灰质（在几个离散的斑块中）、桥脑盖网状核的背外侧翼和口桥网状核。深顶层的其他同侧目标是楔形核和下丘外核。在一些实验中，转运蛋白在黑质中也很明显。轴突构成背脊髓束或背前束，在背侧被盖部内交叉，并在脑干中线略外侧的位置下降。背前束的最亲侧和相当广泛的目标是桥状织网核。当背前束在桥状被内向尾侧运动时，标记轴突进入桥网状核口部和尾部的背侧和内侧区域。在尾髓水平，大部分标记轴突组成的前背束通过腹侧，并在下橄榄核复合体内侧副核的亚核b内大量结束。在它的尾部，只有几个分散的、标记的轴突可以进入颈脊髓。被标记的轴突也通过顶叶连接到达对侧或对侧丘。这样的轴突似乎主要在更深的顶盖层中出现和结束。在1个实验中，注射侵入三叉神经中脑核。标记轴突在运动核、主感觉核（相当丰富）和三叉神经的脊核或降核内明显可见。
The autoradiographic tracing method was used to identify the various descending tectofugal pathways and their targets in the rhesus monkey (M. mulatta). The majority of descending tectofugal axons arise from collicular laminae which lie ventral to the stratum opticum (layer 3). Such descending axons can be grouped into 2 major bundles or tracts, i.e., the ipsilateral tectopontine-tectobulbar tract and the crossed tectospinal tract (or the predorsal bundle). There is, in addition to these 2 major pathways, a smaller, commissural projection. The ipsilateral pathway courses laterally and ventrocaudally to terminate within the parabigeminal nucleus, the mesencephalic reticular formation, the dorsal lateral pontine gray (in several discrete patches), the dorsal lateral wing of the nucleus reticularis tegmenti pontis and the nucleus reticularis pontis oralis. Other ipsilateral targets of the deep tectal layers are the cuneiform nucleus and the external nucleus of the inferior colliculus. In several experiments transported protein is also apparent within the substantia nigra. Axons which comprise the tectospinal tract, or the predorsal bundle, cross within the dorsal tegmental decussation and descend within the brainstem in a position slightly lateral to the midline. The most rostral and quite extensive target of the predorsal bundle is the nucleus reticularis tegmenti pontis. As the predorsal bundle courses caudally within the pontine tegmentum, labeled axons enter the dorsal and medial regions of both the oral and the caudal divisions of the nucleus reticularis pontis. At caudal medullary levels, the majority of the labeled axons comprising the predorsal bundle pass ventrally to end quite profusely within the subnucleus b of the medial accessory nucleus of the inferior olivary complex. Caudal to this only a few scattered, labeled axons can be followed into the cervical spinal cord. Labeled axons also pass to the opposite, or contralateral colliculus via the tectal commissure. Such axons appear to arise and end primarily within the deeper tectal layers. In 1 experiment, the injection invaded the mesencephalic nucleus of the trigeminal nerve. Labeled axons were apparent within the motor nucleus, the chief sensory nucleus (quite profusely) and the spinal or descending nucleus of the trigeminal nerve.