Changes in mesenchymal cell-basal lamina relationships preceding palatal shelf reorientation in the mouse.
Changes in mesenchymal cell-basal lamina relationships preceding palatal shelf reorientation in the mouse.
复制标题
小鼠腭架重新定向之前间充质细胞与基底层关系的变化。
DOI：
10.1002/aja.1001760309
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
Brinkley,LL
中科院分区：
文献类型：
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作者：
Brinkley,LL
次级腭架未来鼻和口腔上皮表面的两个特定区域在架重新定向期间细胞密度增加。检查了间充质细胞与这些区域下方的基底层的关系，并与细胞密度没有变化的相邻区域下方的细胞的关系进行比较。 CD-1 小鼠胎儿在妊娠第 13.5 天获得。一些腭架被立即切除并固定用于电子显微镜检查；其他头部在固定前被部分解剖并孵育 4 小时。尽管仅在 6 小时孵育后才检测到架子移动，但选择较短的时间段是为了检测重新定向之前的事件。对已知上皮细胞密度增加的鼻腔和口腔区域（活性片段）和鼻腔和口腔区域的上皮间质界面（非活性片段）拍摄了电子显微照片。在照相照片上划定的 500 nm 宽区域内进行了多次测量。鼻腔和口腔区域之间的间充质细胞结构存在明显差异。每个区域的活跃和不活跃部分也不同。观察到附着在致密层下表面的丝状层在区域之间的厚度和特性也有所不同。孵育 4 小时后，各区域间充质细胞结构和层下区超微结构的差异明显。这些结果表明，可能由细胞外基质介导的局部上皮-间质相互作用发生在架重新定向之前。间充质细胞构型的这些变化是否实际上反映了架重新定向所必需的间充质细胞活性仍有待阐明。
Two specific regions of the future nasal and oral epithelial surfaces of the secondary palatal shelves increase in cell density during shelf reorientation. The relationships of mesenchymal cells to the basal lamina underlying these regions were examined and compared to those of cells underlying adjacent regions which did not change in cell density. CD‐1 mouse fetuses were obtained on day 13.5 of gestation. Some palatal shelves were excised immediately and fixed for electron microscopy; other heads were partially dissected and incubated for 4 hr prior to fixation. Although shelf movement is detected only after 6 hr incubation, the shorter time period was selected in order to detect events which precede reorientation. Electron micrographs were taken of the epithelial‐mesenchymal interface of nasal and oral regions known to increase in epithelial cell density (active segments) and of nasal and oral regions which did not increase (inactive segments). Several measurements were made in a 500‐nm‐wide zone delimited on photographic prints. Distinct differences in mesenchymal cell configuration were found between nasal and oral regions. Active and inactive segments of each region also differed. A filamentous layer attached to the undersurface of the lamina densa was observed to vary in thickness and character between regions as well. After 4 hr incubation, differences in mesenchymal cell configuration and ultrastructure of the sublaminar zone were apparent between regions. These results suggest that local epithelial‐mesenchymal interactions, possibly mediated by the extracellular matrix, precede shelf reorientation. Whether these changes in mesenchymal cell configuration actually reflect mesenchymal cell activities that are necessary for shelf reorientation remains to be elucidated.