ABSTRACTThe density and size of astrocyte‐, oligodendrocyte‐ and neurone nuclei in corpus striatum were determined in rats with CCl4‐induced liver encephalopathy by means of an electronic image analyzer. After 8 weeks of CCl4‐administration, the astrocyte number had nearly doubled, and astrocytes with increased nuclear size appeared. After 20 weeks, a reduction (appr. 25 per cent) was found in the number of nerve cells and oligodendrocytes. The total number of glial cells, however, was unchanged during the experiment; this demonstrates the need of performing differential counts when evaluating gliosis. Probably, a part of the increase in the number of astrocytes was due to a transformation from precursor cells, usually classified as oligodendrocytes. The increased number and size of astrocyte nuclei are probably connected with an enhanced astrocyte metabolic capacity due to alterations in the ammonia and amino acid met