Department of Biology, Faculty of Sciences, University of A Coruña, Coruña, Spain.
Centro de Investigaciones Científicas Avanzadas (CICA), University of A Coruña, Coruña, Spain.
J Comp Neurol. 2022 Jun;530(8):1164-1194. doi: 10.1002/cne.25268. Epub 2021 Nov 11.
We studied the connections (connectome) of the adult zebrafish pallium using carbocyanine dye tracing and ancillary anatomical methods. The everted zebrafish pallium (dorsal telencephalic area, D) is composed of several major zones (medial, lateral, dorsal, central, anterior, and posterior) distinguishable by their topography, cytoarchitecture, immunohistochemistry, and genoarchitecture. Our comprehensive study reveals poor interconnectivity between these pallial areas, especially between medial (Dm), lateral/dorsal (Dl, Dd), and posterior (Dp) regions. This suggests that the zebrafish pallium has dedicated modules for different neural processes. Pallial connections with extrapallial regions also show compartmental organization. Major extratelencephalic afferents come from preglomerular nuclei (to Dl, Dd, and Dm), posterior tuberal nucleus (to Dm), and lateral recess nucleus (to Dl). The subpallial (ventral, V) zones dorsal Vv, Vd, and Vs, considered homologues of the striatum, amygdala, and pallidum, are mainly afferent to Dl/Dd and Dp. Regarding the efferent pathways, they also appear characteristic of each pallial region. Rostral Dm projects to the dorsal entopeduncular nucleus. Dp is interconnected with the olfactory bulbs. The central region (Dc) defined here receives mainly projections from Dl-Dd and projects toward the pretectum and optic tectum, connections, which help to delimiting Dc. The connectome of the adult pallium revealed here complements extant studies on the neuroanatomical organization of the brain, and may be useful for neurogenetic studies performed during early stages of development. The connectome of the zebrafish pallium was also compared with the pallial connections reported in other teleosts, a large group showing high pallial diversity.
我们使用碳菁染料示踪和辅助解剖方法研究了成年斑马鱼大脑皮层的连接（连接组）。外翻的斑马鱼大脑皮层（背侧端脑区，D）由几个主要区域（内侧、外侧、背侧、中央、前侧和后侧）组成，这些区域可以通过它们的地形学、细胞构筑、免疫组织化学和基因构筑来区分。我们的综合研究表明，这些大脑皮层区域之间的连通性很差，特别是内侧（Dm）、外侧/背侧（Dl、Dd）和后侧（Dp）区域之间。这表明斑马鱼大脑皮层具有用于不同神经过程的专用模块。与外皮层区域的大脑皮层连接也显示出分区组织。主要的外端脑传入来自前脑核（Dl、Dd 和 Dm）、后侧结节核（Dm）和外侧隐窝核（Dl）。亚皮层（腹侧，V）区背侧 Vv、Vd 和 Vs，被认为是纹状体、杏仁核和苍白球的同源物，主要向 Dl/Dd 和 Dp 投射。关于传出通路，它们也似乎是每个大脑皮层区域的特征。前侧 Dm 投射到背侧动眼神经核。Dp 与嗅球相互连接。这里定义的中央区域（Dc）主要接收来自 Dl-Dd 的投射，并向顶盖和视顶盖投射，这些连接有助于限定 Dc。这里揭示的成年大脑皮层连接组补充了现有关于大脑神经解剖组织的研究，并且可能对在早期发育阶段进行的神经遗传学研究有用。我们还将斑马鱼大脑皮层的连接组与其他硬骨鱼类报告的大脑皮层连接进行了比较，这些硬骨鱼类是一个具有高度大脑皮层多样性的大群体。
