Striedter G F
Department of Neurosciences, University of California, San Diego.
Brain Behav Evol. 1990;36(6):355-77. doi: 10.1159/000115319.
In a companion paper, the nuclear organization of the diencephalon of the channel catfish, Ictalurus punctatus, was described and compared to that of other teleosts. The present paper describes the connections of the diencephalon with the retina, optic tectum, corpus of the cerebellum and telencephalon. The principal tracer employed is the indocarbocyanine dye DiI which diffuses along neuronal membranes in fixed tissues. Almost all of the nuclei that were recognized as distinct in the companion study are found to also exhibit distinct sets of connections. Most of these connections have not been described previously in catfishes or other teleosts. When combined with connectional data from the existing literature, the results of the present study allow one to recognize a great number of distinct pathways through the diencephalon of channel catfish, including several visual, auditory, gustatory, electrosensory and mechanosensory pathways to the telencephalon. Almost all of the species differences in diencephalic organization noted in the companion study can be accounted for by changes in one of the major sensory pathways. In contrast, the multimodal and integrative areas of the diencephalon appear to be relatively conservative. A comparison between the diencephalon of teleosts and that of other vertebrates suggests that the dorsal thalamus, the ventral thalamus and the posterior tuberculum are homologous, at least in part, to the dorsal thalamus, the zona incerta and the subthalamic nucleus of mammals, respectively. All three areas project to the telencephalon in both mammals and teleosts. In most vertebrates, however, the dorsal thalamus provides the dominant input to the telencephalon, whereas in teleosts the main telencephalic input derives instead from the posterior tuberculum.
在一篇配套论文中，描述了斑点叉尾鮰间脑的核组织，并将其与其他硬骨鱼的进行了比较。本文描述了间脑与视网膜、视顶盖、小脑体和端脑的连接。主要使用的示踪剂是吲哚花青绿染料DiI，它在固定组织中沿神经元膜扩散。在配套研究中被识别为不同的几乎所有核，在本文中也显示出不同的连接组。这些连接中的大多数以前在鲶鱼或其他硬骨鱼中未曾描述过。当与现有文献中的连接数据相结合时，本研究结果使人们能够识别出通过斑点叉尾鮰间脑的大量不同通路，包括几条通向端脑的视觉、听觉、味觉、电感觉和机械感觉通路。配套研究中指出的间脑组织结构的几乎所有物种差异，都可以通过主要感觉通路之一的变化来解释。相比之下，间脑的多模态和整合区域似乎相对保守。硬骨鱼间脑与其他脊椎动物间脑的比较表明，背侧丘脑、腹侧丘脑和后结节至少部分分别与哺乳动物的背侧丘脑、未定带和丘脑下核同源。在哺乳动物和硬骨鱼中，这三个区域都投射到端脑。然而，在大多数脊椎动物中，背侧丘脑向端脑提供主要输入，而在硬骨鱼中，端脑的主要输入则来自后结节。
