Sattler C A, Sawada N, Sattler G L, Pitot H C
McArdle Laboratory for Cancer Research, University of Wisconsin, Madison 53706.
Hepatology. 1988 Nov-Dec;8(6):1540-9. doi: 10.1002/hep.1840080612.
Primary cultures of adult rat hepatocytes in a serum-free medium were observed by time lapse cinematography to proceed through mitotis and cytokinesis. An ultrastructural study of these cultures is presented with electron micrographs of each stage of mitosis and cytokinesis. The cultured hepatocytes begin to enter prophase about 48 hr after plating and proceed through mitosis in approximately 70 min not including cytokinesis. During this time, they remain somewhat flattened and joined to neighboring cells rather than rounding up. Both mononucleate and binucleate hepatocytes proceed through mitosis. Some mononucleate cells do not undergo cytokinesis, resulting in the formation of binucleate cells. In binucleate hepatocytes, both nuclei proceed through prophase simultaneously. Usually a single mitotic spindle with a large metaphase plate containing chromosomes from both nuclei is observed. Cytokinesis frequently occurs in binucleate hepatocytes which have a single mitotic spindle. Some binucleate cells form tripolar or 4-polar metaphase plates. In tripolar metaphases, some cells do not divide, resulting in multinucleate cells, whereas others undergo cytokinesis yielding three mononucleate cells or one binucleate and one mononucleate cell. Two mitotic spindles located perpendicularly to each other with microtubules intertwining have been observed in 4-polar metaphases. In this latter case, no cytokinesis has been observed. This study shows that both mononucleate and binucleate adult rat hepatocytes cultured in a serum-free medium in the presence of epidermal growth factor not only synthesize DNA, but progress through mitosis and often cytokinesis.
通过延时摄影观察无血清培养基中成年大鼠肝细胞的原代培养物，发现其经历有丝分裂和胞质分裂过程。本文呈现了这些培养物的超微结构研究，配有有丝分裂和胞质分裂各阶段的电子显微镜照片。培养的肝细胞在接种后约48小时开始进入前期，并在大约70分钟内完成有丝分裂（不包括胞质分裂）。在此期间，它们仍保持 somewhat flattened 状态并与相邻细胞相连，而不是变圆。单核和双核肝细胞都能进行有丝分裂。一些单核细胞不进行胞质分裂，从而形成双核细胞。在双核肝细胞中，两个细胞核同时进入前期。通常会观察到一个单一的有丝分裂纺锤体，带有一个大的中期板，其中包含来自两个细胞核的染色体。胞质分裂经常发生在具有单个有丝分裂纺锤体的双核肝细胞中。一些双核细胞形成三极或四极中期板。在三极中期，一些细胞不分裂，形成多核细胞，而另一些细胞进行胞质分裂，产生三个单核细胞或一个双核细胞和一个单核细胞。在四极中期观察到两个相互垂直的有丝分裂纺锤体，其微管相互缠绕。在后一种情况下，未观察到胞质分裂。这项研究表明，在无血清培养基中、在表皮生长因子存在的情况下培养的成年大鼠单核和双核肝细胞不仅能合成DNA，还能进行有丝分裂，并且经常进行胞质分裂。 （注：“somewhat flattened”直译为“有点扁平”，结合语境这里可能是指细胞形态有点扁平状 ；“progress through”直译为“通过……进展”，这里意译为“进行”更符合语境 ）
