Innes P B
J Embryol Exp Morphol. 1978 Feb;43:185-94.
The ultrastructure of the mesenchymal element of the palatal shelves of C3H mouse embryos aged 13 days 18 h and 14 days 18 h in utero was studied. At 13 days 18 h the mesenchyme showed a high density of cells. The cells contained a well developed system of rough endoplasmic reticulum and Golgi complex; many were ciliated and multi-vescular structures were common. By 14 days 18 h, many of the mesenchymal cells contained large numbers of glycogen particles. These cells also possessed long cytoplasmic processes which sometimes were seen to contain many filaments 5--7 nm in diameter. Some of the cells also contained a fine filamentous network just below the plasma membrane. Developing mononuclear and binucleate skeletal muscle cells containing myofibrils were present in the posterior region of the palate, with groups of cells which consisted of typical peripheral neurons and their surrounding satellite cells. Both the muscle and nerve cells were only observed in the 14 day 18 h material. It is suggested that both the myofibrils in the skeletal muscle cells and the filamentous network in the mesenchymal cells may play a role in shelf reorientation.
对子宫内13天18小时和14天18小时龄的C3H小鼠胚胎腭突间充质成分的超微结构进行了研究。在13天18小时时，间充质细胞密度较高。细胞含有发育良好的粗面内质网和高尔基体系统；许多细胞有纤毛，多囊泡结构很常见。到14天18小时时，许多间充质细胞含有大量糖原颗粒。这些细胞还具有长的细胞质突起，有时可见其中含有许多直径为5 - 7纳米的细丝。一些细胞在质膜下方还含有精细的丝状网络。在腭后部存在含有肌原纤维的正在发育的单核和双核骨骼肌细胞，以及由典型的周围神经元及其周围卫星细胞组成的细胞群。肌肉和神经细胞仅在14天18小时的材料中观察到。有人提出，骨骼肌细胞中的肌原纤维和间充质细胞中的丝状网络可能在腭突重新定向中起作用。
