Zhang H Y, Hoffmann K P
Allgemeine Zoologie und Neurobiologie, Ruhr-Universität Bochum, FRG.
Eur J Neurosci. 1993 May 1;5(5):486-500. doi: 10.1111/j.1460-9568.1993.tb00515.x.
Retinal projections to the pretectal nuclei, accessory optic system and superior colliculus in pigmented and albino ferrets were studied using anterograde tracing techniques. Both Nissl- and myelin-stained material was used to identify the pretectal nuclei, nuclei of the accessory optic system and the layers of the superior colliculus. Following monocular injection of either horseradish peroxidase or rhodamine-B-isothiocyanate, four pretectal nuclei, including the nucleus of the optic tract, posterior pretectal nucleus, anterior pretectal nucleus and the olivary pretectal nucleus, could be identified to receive direct retinal input in both pigmented and albino strains. In the accessory optic system, retinal terminals were observed in the dorsal, lateral and medial terminal nuclei as well as in the interstitial nucleus of the superior fasciculus, posterior fibres. The retinal projection to the superior colliculus was found to innervate the three superficial layers. The retinal projections to the pretectal nuclei and nuclei of the accessory optic system in the pigmented animals were bilateral, although the label was most dense contralateral to the injected eye. Ipsilateral retinal projections to the pretectal nuclei and nuclei of the accessory optic system appeared to be absent in albino ferrets, i.e. they were invisible with our methods. In both pigmented and albino ferrets retinal terminals in the contralateral superior colliculus densely innervated the three superficial layers. In both strains the ipsilateral projection appeared as clusters which were absent in rostral and caudal poles. In pigmented animals the ipsilateral projection was much denser and more extensive than in albinos. Following injection of retrograde tracers into the brainstem at the level of the dorsal cap of the inferior olive, retrogradely labelled neurons in the pretectum were found in the ipsilateral nucleus of the optic tract. Their somata overlapped mainly with scattered retinal terminals close to the pretectal surface and rarely or not all with the deeper prominent terminal clusters. In the accessory optic system, inferior olive projecting neurons were observed in all four ipsilateral nuclei and fully coincided with the retino-recipient zones. In the superior colliculus, retrogradely labelled neurons were found contralateral to the injection site in the deep layers.
利用顺行追踪技术研究了有色和白化雪貂视网膜向顶盖前核、附属视系统和上丘的投射。尼氏染色和髓鞘染色材料均用于识别顶盖前核、附属视系统核以及上丘的各层。在单眼注射辣根过氧化物酶或异硫氰酸罗丹明 - B后，可识别出四个顶盖前核，包括视束核、顶盖后核、顶盖前核和橄榄顶盖前核，在有色和白化品系中均可接受视网膜的直接输入。在附属视系统中，在背侧、外侧和内侧终核以及上丘臂间质核、后纤维中观察到视网膜终末。发现视网膜向上丘的投射支配上丘的三个浅层。有色动物中视网膜向顶盖前核和附属视系统核的投射是双侧的，尽管标记在注射眼对侧最为密集。白化雪貂中似乎不存在视网膜向顶盖前核和附属视系统核的同侧投射，即使用我们的方法无法观察到。在有色和白化雪貂中，对侧侧上丘的视网膜终末密集支配三个浅层。在两个品系中，同侧投射均表现为簇状，在头端和尾端极区不存在。在有色动物中，同侧投射比白化动物更密集、更广泛。在橄榄下核背帽水平向脑干注射逆行示踪剂后，在同侧视束核中发现顶盖前区有逆行标记的神经元。它们的胞体主要与靠近顶盖前表面的散在视网膜终末重叠，很少或并非全部与更深层突出的终末簇重叠。在附属视系统中，在所有四个同侧核中均观察到投射到下橄榄的神经元，且与视网膜接受区完全重合。在上丘中，在注射部位对侧的深层发现逆行标记的神经元。
