Morphology of nuclear ribonucleoproteins in the early period of liver regeneration.

A cytochemical study on the nuclei of hepatocytes in the regenerating liver after partial hepatectomy by the method of Higgins and Anderson was carried out. The behaviour of the ribonucleoprotein components of the nucleus, using EDTA according to Bernhard, revealed altered proportions of the fibrillar and granular components of the nucleoli in the early phase of regeneration and morphologic changes in nuclear RNP, especially in perichromatin fibrils. At 6 h after hepatectomy, the reaction with perichromatin fibrils (FP) was intense, localized around fields of condensed chromatin, which suggests intense transcription of extranucleolar RNA. The behaviour of the remaining nuclear ribonucleoproteins was uncharacteristic.