Effect of ethanol on nucleolar structure: a cytological indication of change in RNA/protein synthesis

The effects of chronic ethanol ingestion on an organelle known to be involved in protein synthesis were studied cytologically in nerve cells of the adult hamster. Twenty-six animals were administered standard laboratory chow and either tap water (controls) or a 15% ethanol solution (experimentals) for a period of 7 weeks. Brains were perfusion-fixed, sectioned transversely, and stained with buffered thionin for microscopic analysis. Reported here are changes in an RNA-rich intranucleolar body (INB) seen in facial motor neurons and cerebellar Purkinje cells of the golden hamster. After chronic ethanol ingestion, the size and frequency of the INB increased significantly in both cell populations. Theoretical considerations are discussed concerning the correlation between this apparent storing of nucleolar RNA/RNP and the biochemical evidence of other investigators for ethanol-induced alterations in RNA/protein synthesis and utilization in neurons.