Scanning electron microscopic study of degeneration and regeneration in the olfactory epithelium after axotomy.
Scanning electron microscopic study of degeneration and regeneration in the olfactory epithelium after axotomy.
复制标题
轴索切除术后嗅上皮变性和再生的扫描电子显微镜研究。
DOI：
10.1007/bf01190842
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Costanzo,RM
中科院分区：
文献类型：
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作者：
Morrison,EE;Costanzo,RM
用扫描电子显微镜观察了嗅神经切断后成年金黄地鼠的嗅觉上皮。轴突切断会导致成熟嗅觉神经元的退行性变性。变性高峰出现在第4天左右。在变性期间，上皮主要由支持细胞和基底细胞组成。微绒毛柱状支持细胞具有从其侧缘延伸至邻近细胞的细小细胞突起。支持细胞延伸到基板，在那里它们终止于形态各异的足突状突起(棍状、张开和钩状)。基底膜附近可见基底层细胞长出新的替代嗅觉神经元。它们的细胞表面粗糙，覆盖着小颗粒和细小的细胞延伸。鲍曼氏腺导管细胞不分叉地延伸穿过上皮，在那里它们形成复盖着微绒毛的漏斗管开口。在恢复期早期(5-30天)，下层上皮区的嗅觉神经元数量增加。我们观察到嗅觉神经元具有发育中的轴突和树突。顶端可见特化的生长锥体结构。嗅觉神经元生长锥体呈细长或棒状，表面有褶皱的膜。几个细丝足从生长锥体延伸出来，与相邻细胞接触。在恢复后期(35-120天)，嗅觉神经元在中上皮区和下上皮区明显增多。许多树突状突起延伸到上皮表面，并终止于节状纤毛结构。嗅轴突基底部穿过，形成小的上皮内束，穿过基底板，然后在固有板内聚集成较大的束。本研究提供了神经元损伤后嗅觉上皮的详细三维观察，并描述了神经退行性变化，嗅神经元的替换，发育和成熟。此外，我们还描述了支持细胞的结构和基底附着，以及它们与嗅神经元的神经胶质样关系。
The olfactory epithelium of the adult hamster (Mesocricetus auratus) was examined with the scanning electron microscope following olfactory nerve axotomy. Axotomy results in retrograde degeneration of mature olfactory neurons. Maximum degeneration was observed around day 4. During the degeneration period the epithelium consists primarily of supporting and basal cells. Microvillar columnar supporting cells were observed to have fine cellular processes extending from their lateral border to neighbouring cells. Supporting cells extended to the basal lamina where they terminated in foot-like processes of variable shapes (club, splay and hook). Basal cells which gave rise to new replacement olfactory neurons were observed near the basal lamina. They had a rough cellular surface covered with small granules and fine cellular extensions. Bowman's gland duct cells extended unbranched through the epithelium where they formed funnel duct openings covered with microvilli. During early recovery periods (5–30 days) the number of olfactory neurons in the lower epithelium region increased. We observed olfactory neurons with developing axon and dendritic processes. Specialized growth cone structures were seen at the tips. Olfactory neuron growth cones were elongated or club-shaped and had a ruffled membrane surface. Several thin filopodia extended from the growth cone and made contact with adjacent cells. At late recovery periods (35–120 days) there was a marked increase in the number of olfactory neurons within the middle and lower epithelium regions. Numerous dendritic processes extended to the epithelial surface and terminated in knob-like ciliated structures. Olfactory axons passed basally, forming small intra-epithelial bundles that penetrated the basal lamina then fasciculated into larger bundles within the lamina propria.This study provides detailed three-dimensional observations of the olfactory epithelium following neuron injury, and describes neural degenerative changes, replacement of olfactory neurons, development and maturation. In addition, we describe the structure and basal attachment of supporting cells and their glial-like relation with olfactory neurons.