CAUNA N, ROSS L L
J Biophys Biochem Cytol. 1960 Oct;8(2):467-82. doi: 10.1083/jcb.8.2.467.
Thin slices of the finger pads of six individuals were fixed in buffered 1 per cent osmic acid, embedded in deaerated, nitrogenated methacrylate, and cut into thin sections for electron microscopic study. Before embedding, the slices were trimmed so as to include several digital tactile corpuscles. Some thin sections were stained in 10 per cent aqueous phosphotungstic acid solution. The principal part of Meissner's corpuscle is made up of flattened laminar cells stretching across the corpuscle in irregular layers. The perinuclear cytoplasm of these cells contains numerous small mitochondria, a sparse granular endoplasmic reticulum, and a large number of small vesicles. Nerve fibers enter the side or base of the corpuscle, lose their myelin sheaths, and follow a meandering course between the laminar cell plates. The nerve endings enter into a close appositional relationship with the flattened portions of the laminar cells. In some areas the apposed axolemma and cell membranes are slightly thickened with small vesicles located along the cell membrane or on both surfaces. These regions are interpreted as synapses. The most prominent feature of the nerve endings is an extraordinary accumulation of small mitochondria which vary in size and internal density. The nerve endings also contain vacuoles, groups of dense concentric membranes, and small dense vesicles of irregular distribution. The laminar cells are separated from one another by a dense intercellular substance of uniform thickness which also envelops the entire corpuscle. This material contains randomly oriented collagen fibers and fine fibrils bound together by a dense material at nodal points recurring at regular intervals of approximately 120 mmicro. These findings are discussed in relation to the problems of the function of Meissner's corpuscle, neural material loss and replacement, and the presence of synapses.
取6名个体的指腹薄片，用1%的缓冲锇酸固定，包埋于脱气、充氮的甲基丙烯酸酯中，切成薄片用于电子显微镜研究。包埋前，将切片修整以包含几个指腹触觉小体。一些薄片用10%的磷钨酸水溶液染色。迈斯纳小体的主要部分由扁平的层状细胞组成，这些细胞以不规则的层次横跨小体伸展。这些细胞的核周细胞质含有许多小线粒体、稀疏的颗粒内质网和大量小泡。神经纤维进入小体的侧面或基部，失去髓鞘，并在层状细胞板之间蜿蜒前行。神经末梢与层状细胞的扁平部分形成紧密的并列关系。在一些区域，并列的轴膜和细胞膜略有增厚，沿细胞膜或两侧有小泡。这些区域被解释为突触。神经末梢最显著的特征是大小和内部密度各异的小线粒体异常聚集。神经末梢还含有液泡、密集的同心膜群和分布不规则的小致密小泡。层状细胞被一层厚度均匀的致密细胞间质分隔开，该间质也包裹着整个小体。这种物质含有随机排列的胶原纤维和细纤维，它们在节点处由致密物质结合在一起，节点以大约120微米的规则间隔重复出现。结合迈斯纳小体的功能、神经物质的损失和替代以及突触的存在等问题对这些发现进行了讨论。
