Nucleolar changes induced by isoproterenol in mouse acinar parotid cells

This paper deals with the analysis of the nucleolar morphology and distribution of the nucleolar component (i.e. fibrils and granules) in normal and isoproterenol-treated parotid acinar cells of mice. Normally nucleoli present both components intermingled, but at 2 h treatment a considerable decrease of the fibrillar area is detected by a silver staining method. Normal nucleolar characteristics are recovered after eight hours treatment. In hypertrophic cells nucleolar size is considerably increased, but the ratio total nucleolar area/fibrillar area is similar to control cells as shown by a stereometrical computerized analysis. Rounded nucleolar bodies occur in these nuclei which do not seem to be dependent on the modifications induced by the drug.