Rapisardi S C, Miles T P
J Comp Neurol. 1984 Mar 10;223(4):515-34. doi: 10.1002/cne.902230405.
We have made a fine structural investigation of the synaptic patterns made by axon terminals of retinal ganglion cells in the dorsal lateral geniculate nucleus of the cat. We compared the retinal input to dendritic processes that bear clusters of large appendages with the retinal input to relatively smooth dendritic segments that have only a few isolated spines. The study was restricted to the portion of laminae A and A1 that receive central visual field input. We were able to completely reconstruct 33 individual terminal boutons from long series of consecutive thin sections. Retinal terminals that were presynaptic to dendritic appendages tended to occupy the central position in the complex synaptic zones of geniculate fine structure called glomeruli. These terminals were surrounded by significantly more profiles than retinal terminals that were presynaptic to dendritic stems and averaged twice as many synaptic contacts per terminal bouton. The retinal input to dentritic appendages was heavily involved in a specific synaptic pattern called the triadic arrangement while retinal input to dendritic stems was only lightly involved in triads. Dendritic appendages in triads received greater synaptic input from profiles with flattened vesicles than did the dendritic stems that were found in triads.
我们对猫背外侧膝状核中视网膜神经节细胞轴突终末形成的突触模式进行了精细的结构研究。我们比较了视网膜对带有大附属物簇的树突状突起的输入与视网膜对相对平滑、仅有少数孤立棘突的树突段的输入。该研究局限于接受中央视野输入的A层和A1层部分。我们能够从一系列连续的薄切片中完整重建33个单个终末小体。与树突干形成突触前联系的视网膜终末往往占据膝状核精细结构中称为肾小球的复杂突触区的中心位置。这些终末周围的轮廓明显多于与树突干形成突触前联系的视网膜终末，每个终末小体的突触接触平均多两倍。视网膜对树突状附属物的输入大量参与一种称为三联体排列的特定突触模式，而视网膜对树突干的输入仅少量参与三联体。三联体中的树突状附属物比三联体中的树突干从具有扁平囊泡的轮廓接受更多的突触输入。
