Mize R R, Horner L H
J Comp Neurol. 1984 Apr 20;224(4):579-90. doi: 10.1002/cne.902240407.
The retinal terminals of the medial interlaminar nucleus (MIN) and ventral lateral geniculate nucleus ( VLG ) have been examined quantitatively to determine if there are morphological differences in their synaptic ultrastructure which reflect their distinctive physiologies . The cross-sectional area and density (number per unit area) of synaptic contact zones with conventional and presynaptic dendrites (F2 profiles) were measured for each retinal terminal. The densities of F2 presynaptic dendrites and F1 flattened vesicle axon terminals were also measured. Retinal terminals in MIN were often large (mean size = 2.7 micron2 area) and had a high density of synaptic contacts (0.14 per micron surface area) with conventional dendrites, presynaptic dendrites, and dendritic spines. A high density of F2 presynaptic dendrites (0.08 per micron2 area) was found in MIN. F1 axon terminals were also found frequently (0.04 per micron2). MIN retinal terminals were often organized in glomeruli like those of the dorsal lateral geniculate nucleus. The retinal terminals in VLG were almost always small (mean size = 0.94 micron2 area), although they also had a high density of synaptic contacts (0.17 per micron surface area). They frequently synapsed on small dendrites and dendritic spines and less frequently on large dendrites. Unlike MIN, retinal terminals in VLG rarely contacted F2 presynaptic dendrites which were much less frequent in VLG (0.01 per micron2 area). Like MIN, VLG contained numerous F1 axon terminals (0.06 per micron2 area). No typical retinal glomeruli were found in VLG . These results show that MIN, which contains many Y cells, has a population of large retinal terminals and many F2 presynaptic dendrites. VLG , which apparently has only W cells, contains only small retinal terminals and has fewer F2 presynaptic dendrites. Both have a high density of F1 flat vesicle axon terminals.
对内侧层间核（MIN）和腹侧外侧膝状体核（VLG）的视网膜终末进行了定量研究，以确定它们的突触超微结构是否存在形态学差异，这些差异反映了它们独特的生理学特性。测量了每个视网膜终末与传统树突和突触前树突（F2分布图）的突触接触区的横截面积和密度（每单位面积的数量）。还测量了F2突触前树突和F1扁平囊泡轴突终末的密度。MIN中的视网膜终末通常较大（平均面积 = 2.7平方微米），与传统树突、突触前树突和树突棘的突触接触密度较高（每平方微米表面积0.14个）。在MIN中发现F2突触前树突的密度较高（每平方微米面积0.08个）。F1轴突终末也经常出现（每平方微米0.04个）。MIN视网膜终末通常像背侧外侧膝状体核的终末一样排列成小球状。VLG中的视网膜终末几乎总是很小（平均面积 = 0.94平方微米），尽管它们也有较高的突触接触密度（每平方微米表面积0.17个）。它们经常与小树突和树突棘形成突触，与大树突形成突触的频率较低。与MIN不同，VLG中的视网膜终末很少接触F2突触前树突，F2突触前树突在VLG中要少得多（每平方微米面积0.01个）。与MIN一样，VLG含有大量F1轴突终末（每平方微米面积0.06个）。在VLG中未发现典型的视网膜小球。这些结果表明，含有许多Y细胞的MIN有一群大的视网膜终末和许多F2突触前树突。显然只含有W细胞的VLG只含有小的视网膜终末，且F2突触前树突较少。两者都有高密度的F1扁平囊泡轴突终末。
