ABSTRACTThe nuclei of Purkinje cells and Bergmann astrocytes were counted on sagittal sections from cerebellum and the length of stratum gangliosum was measured in rats with CCl4‐induced liver disease, using an electronic image analyzer. After 8 weeks of CCl4‐administration a reduction was found in the number of Purkinje cells, many of which showed homogenizating changes. Ten weeks after termination of the administration period the number of Purkinje cells was reduced by 12 per cent. The number of Bergmann astrocytes remained significantly increased after 8 weeks of CCl4‐administration (max. 20 per cent). The changes of Purkinje cell and Bergmann astrocyte density developed during the period of severe liver necrosis, whereas only minor changes were found in the ensuing period of liver “cirrhosis”. In the perfusion fixed specimens, the Bergmann astrocyte nuclei increased in volume up to 65 per cent and immersion fixed brains showed typical Alzheimer type II nuclear changes. The impact of the increased plasma ammonia concentration on the astrocytes is