SYNAPTIC ORGANIZATION IN THE LATERAL GENICULATE NUCLEUS OF THE MONKEY
SYNAPTIC ORGANIZATION IN THE LATERAL GENICULATE NUCLEUS OF THE MONKEY
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DOI：
10.1007/bf00339284
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发表时间：
1964-01-01
期刊：
影响因子：
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通讯作者：
GUILLERY, RW
中科院分区：
文献类型：
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作者：
COLONNIER, M;GUILLERY, RW
用电子显微镜研究了猴外侧膝状体核内的突触结构，可以通过其所含的突触囊泡以及它们与邻近神经突起的特殊接触来识别外侧膝状体核内的轴突终末。两种类型的轴突终末已被确认。第一种类型相对较大（3-20μ），含有相对苍白的线粒体，大量的囊泡，在正常材料中，有一小束神经丝。这些终端被称为LP终端。第二类较小（1-3μ），含有较暗的线粒体，突触囊泡，没有神经丝。这两种类型的终末都形成专门的轴-体和轴-树突突触接触，但轴-体接触相对较少。此外，LP终末经常与SD终末进行特殊的接触，即轴-轴接触，在这些接触处，膜的不对称性使得LP终末必须被认为是SD终末的突触前接触，大多数突触接触与先前描述的接触相同（Gray，1959和1963 a），但除此之外，还发现了一种新的接触类型，其特征是神经丝靠近突触后膜，突触后膜不规则增厚。这种“丝状”接触仅见于LP终末与树突或索马接触的地方。摘除一只眼后的变性表明LP终末是视神经纤维的终末。SD终末的起源尚不清楚，胶质细胞通常在神经突起周围形成薄层，并倾向于分离突触复合体。这些髓鞘偶尔显示出类似于髓磷脂的复杂的同心组织。
The synaptic organization in the lateral geniculate nucleus of the monkey has been studied by electron microscopy.The axon terminals in the lateral geniculate nucleus can be identified by the synaptic vesicles that they contain and by the specialized contacts that they make with adjacent neural processes. Two types of axon terminal have been recognized. The first type is relatively large (from 3–20μ) and contains relatively pale mitochondria, a great many vesicles and, in normal material, a small bundle of neurofilaments. These terminals have been calledLPterminals. The second type is smaller (1–3μ), contains darker mitochondria, synaptic vesicles, and no neurofilaments. These have been calledSDterminals.Both types of terminal make specialized axo-somatic and axo-dendritic synaptic contacts, but the axo-somatic contacts are relatively rare. In addition theLPterminals frequently make specialized contacts with theSDterminals, that is, axo-axonal contacts, and at these contacts the asymmetry of the membranes is such that theLPterminal must be regarded as pre-synaptic to theSDterminal.The majority of the synaptic contacts are identical to those that have been described previously (Gray, 1959 and 1963a) but, in addition, a new type of contact has been found. This is characterized by neurofilaments that lie close to the post-synaptic membrane, and by an irregular post-synaptic thickening. Such “filamentous” contacts have been found only where anLPterminal contacts a dendrite or a soma.The degeneration that follows removal of one eye demonstrates that theLPterminals are terminals of optic nerve fibres. The origin of theSDterminals is not known.The glial cells often form thin lamellae around the neural processes and tend to isolate synaptic complexes. These lamellae occasionally show a complex concentric organization similar to that of myelin.