Hoyes A D, Riches D J
Haematologia (Budap). 1975;9(3-4):179-93.
The differentiation of the megakaryocyte was studied at the ultrastructural level in the liver of human fetuses of between 49 and 134 mm crown-rump length. The development of the cells was traced from lymphoid elements with the features of haemopoietic stem cells and was divided on the basis of nuclear morphology into three stages. Granule formation commenced during the first stage and demarcation membrances could be demonstrated in the perinuclear cytoplasm early in the second stage. Late stage 2 cells often contained more than one nucleus, and the possibility that this was due to cellular fusion is discussed. The third stage was characterized by the appearance of cytoplasmic zoning and by the gradual extension of the demarcation system throughout the cytoplasm. There was evidence that the demarcation membrances were initially formed directly from the Golgi apparatus, but that their further development was due to the incorporation of elements of the agranular endoplasmic reticulum. The surface projections associated with platelet release were observed only in fully developed cells, and the formation of a zone of clear cytoplasm at the periphery was related to events occurring during the later stages of platelet release.
在头臀长49至134毫米的人类胎儿肝脏中，在超微结构水平上研究了巨核细胞的分化。细胞的发育从具有造血干细胞特征的淋巴样成分开始追踪，并根据核形态分为三个阶段。颗粒形成在第一阶段开始，在第二阶段早期核周细胞质中可显示出分界膜。第二阶段后期的细胞通常含有不止一个细胞核，并讨论了这可能是由于细胞融合的原因。第三阶段的特征是出现细胞质分区以及分界系统逐渐扩展至整个细胞质。有证据表明分界膜最初直接由高尔基体形成，但其进一步发育是由于无颗粒内质网成分的并入。仅在完全发育的细胞中观察到与血小板释放相关的表面突起，周边透明细胞质区域的形成与血小板释放后期发生的事件有关。
