DEVELOPMENTAL CHANGES IN THE ACTIVITY OF GLUTATHIONE S-TRANSFERASE AND ITS IMMUNOCYTOCHEMICAL LOCALIZATION IN THE HYPOPLASTIC CEREBELLUM OF JAUNDICED GUNN RATS

Developmental changes in the activity of glutathione S-transferase (GST) and its immunocytochemical localization were studied in the cerebella of homozygous (j/j) and heterozygous (j/+) Gunn rats. The activity of jaundiced j/j rats began to increase after 8 days of life and reached twice as high as that of non-jaundiced j/+ rats at 15-20 days, chronologically coincident with the development of bilirubin cerebellopathy. When j/j rats were prevented from cerebellopathy by photoirradiation to the newborns from 4 to 7 days, the increase did not occur in spite of yet prolonged jaundice. DE-52 chromatography of the cerebellar 105,000 ｇ supernatant from either j/+ or j/j rats revealed four main activity peaks, and the relative amount of each peak did not differ significantly between the two groups of rats. Immunocytochemical studies with anti-GST antibody showed staining of astoroglial and ependymal cells in the cerebella of both groups of rats. Staining was more extensive in j/j rats than in j/+ rats. The present results suggest that the increase in the cerebellar GST activity in jaundiced Gunn rats is ascribed to hypertrophy or proliferation of astroglial cells, a consepuence of bilirulin neurotoxicity.