[Nuclear ultrastructure of binuclear and trinuclear hepatocytes]

Binucleated and less frequently trinucleated hepatocytes appear in human and animal livers under normal conditions as well as in pathological cases. To provide further ultrastructural data hepatocyte nuclei were investigated in different pathological states. Important results of this study are: Size of the nuclei and structure of the karyoplasm as well as size and localization of the nucleolus are obviously, same in most of the binucleated hepatocytes. In a small percentage of hepatocytes the following findings have been made: One of the nuclei will be light microscopically overlooked due to its small size pretending mononucleated cells. The disappearance of one of the nuclei results in an increase of the number of mononucleated cells and should therefore be evaluated like a decrease of binucleated hepatocytes: a pathological incident. Functional differences between both nuclei become morphologically obvious during virus replication, e.g. HBc-particle production is restricted to one of the nuclei. These results seem to consist rather with amitotic than mitotic cell division.