Aparicio M-Auxiliadora, Saldaña Enrique
Department of Cell Biology and Pathology, Medical School, University of Salamanca, 37007, Salamanca, Spain.
Brain Struct Funct. 2014 Mar;219(2):607-30. doi: 10.1007/s00429-013-0522-x. Epub 2013 Mar 7.
The tectal longitudinal column (TLC) is a longitudinally oriented, long and narrow nucleus that spans the paramedian region of the midbrain tectum of a large variety of mammals (Saldaña et al. in J Neurosci 27:13108-13116, 2007). Recent analysis of the organization of this region revealed another novel nucleus located immediately dorsal, and parallel, to the TLC. Because the name "tectal longitudinal column" also seems appropriate for this novel nucleus, we suggest the TLC described in 2007 be renamed the "ventral tectal longitudinal column (TLCv)", and the newly discovered nucleus termed the "dorsal tectal longitudinal column (TLCd)". This work represents the first characterization of the rat TLCd. A constellation of anatomical techniques was used to demonstrate that the TLCd differs from its surrounding structures (TLCv and superior colliculus) cytoarchitecturally, myeloarchitecturally, neurochemically and hodologically. The distinct expression of vesicular amino acid transporters suggests that TLCd neurons are GABAergic. The TLCd receives major projections from various areas of the cerebral cortex (secondary visual mediomedial area, and granular and dysgranular retrosplenial cortices) and from the medial pretectal nucleus. It densely innervates the ipsilateral lateral posterior and laterodorsal nuclei of the thalamus. Thus, the TLCd is connected with vision-related neural centers. The TLCd may be unique as it constitutes the only known nucleus made of GABAergic neurons dedicated to providing massive inhibition to higher order thalamic nuclei of a specific sensory modality.
顶盖纵柱（TLC）是一个纵向排列的狭长核团，跨越多种哺乳动物中脑顶盖的旁正中区域（萨尔达尼亚等人，《神经科学杂志》，2007年，第27卷，第13108 - 13116页）。最近对该区域组织结构的分析揭示了另一个新的核团，它位于TLC的紧邻背侧且与之平行。由于“顶盖纵柱”这个名称似乎也适用于这个新核团，我们建议将2007年描述的TLC重新命名为“腹侧顶盖纵柱（TLCv）”，而将新发现的核团称为“背侧顶盖纵柱（TLCd）”。这项工作代表了对大鼠TLCd的首次特征描述。一系列解剖学技术被用于证明TLCd在细胞结构、髓鞘结构、神经化学和神经传导方面与其周围结构（TLCv和上丘）不同。囊泡氨基酸转运体的独特表达表明TLCd神经元是γ-氨基丁酸能的。TLCd接受来自大脑皮层各个区域（次级视觉内侧中间区域、颗粒状和非颗粒状压后皮质）以及内侧顶盖前核的主要投射。它密集地支配丘脑同侧的外侧后核和背外侧核。因此，TLCd与视觉相关神经中枢相连。TLCd可能是独特的，因为它是唯一已知的由γ-氨基丁酸能神经元组成的核团，专门为特定感觉模态的高阶丘脑核提供大量抑制作用。
