Jiang Z D, King A J, Moore D R
University of Laboratory of Physiology, Oxford, UK.
Brain Res. 1996 Dec 16;743(1-2):217-32. doi: 10.1016/s0006-8993(96)01042-6.
Unilateral, discrete injections of red and green fluorescent latex microspheres or injections of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) were made into the ferret's superior colliculus (SC) to characterize the topographic organization of the projection from the parabigeminal nucleus (PBN). Retrograde labelling in the PBN revealed that this nucleus projects bilaterally to the SC, although the heaviest projection arises from the ipsilateral PBN. The PBN-SC projection demonstrates a highly ordered organization along the rostral-caudal axis; rostral PBN projects to rostral SC and caudal PBN projects to caudal SC. The caudoventral and rostrodorsal areas of the PBN project mainly to the ipsilateral and contralateral SC, respectively. The ipsilateral pathway terminates principally in the caudal region of the SC, while the contralateral projection terminates predominantly in rostral SC. Ipsilaterally, there are slightly more neurons, located mainly in the ventral PBN, that project to the lateral SC than those, located largely in the dorsal part of the nucleus, that target the medial SC. The contralateral PBN mainly projects to the rostrolateral quadrant of the SC. These results indicate that each quadrant of the SC is innervated principally by a restricted part of the PBN: the caudolateral quadrant, which receives the heaviest ipsilateral input, and the caudomedial quadrant are targeted predominantly by the ventral and dorsal portions, respectively, of the ipsilateral PBN; the rostrolateral quadrant by the contralateral PBN, and the rostromedial quadrant, which receives the weakest input, by the dorsal portion of the nucleus on both sides. These findings suggest that activity in the PBN is relayed to distinct regions of the SC in the form of a highly ordered topographic projection. The adjacent lateral tegmentum (ALT) also projects heavily to the SC, principally on the ipsilateral side. The ALT projection to the ipsilateral SC appears to be organized in a less orderly fashion, and terminates principally in caudal SC, particularly the caudolateral quadrant. No topography was apparent for the contralateral projection.
将红色和绿色荧光乳胶微球单侧、离散注射到雪貂的上丘（SC），或将与辣根过氧化物酶结合的小麦胚凝集素（WGA-HRP）注射到雪貂的上丘，以表征来自双侧顶盖旁核（PBN）投射的拓扑组织。PBN中的逆行标记显示，该核向双侧投射到SC，尽管最强的投射来自同侧PBN。PBN-SC投射沿前后轴呈现高度有序的组织；PBN前部投射到SC前部，PBN后部投射到SC后部。PBN的尾腹侧和嘴背侧区域分别主要投射到同侧和对侧SC。同侧通路主要终止于SC的尾部区域，而对侧投射主要终止于SC的前部。在同侧，投射到外侧SC的神经元略多，主要位于PBN腹侧，而投射到内侧SC的神经元主要位于核的背侧。对侧PBN主要投射到SC的嘴外侧象限。这些结果表明，SC的每个象限主要由PBN的一个受限部分支配：尾外侧象限接受最强的同侧输入，尾内侧象限分别主要由同侧PBN的腹侧和背侧部分支配；嘴外侧象限由对侧PBN支配，而接受最弱输入且位于嘴内侧象限的区域由两侧核的背侧部分支配。这些发现表明，PBN中的活动以高度有序的拓扑投射形式传递到SC的不同区域。相邻的外侧被盖（ALT）也大量投射到SC，主要是在同侧。ALT对同侧SC的投射似乎组织得不太有序，主要终止于SC的尾部，特别是尾外侧象限。对侧投射没有明显的拓扑结构。
