抄録
High dose (500mg/kg) and low dose (300mg/kg) of 2, 5-hexanedione were orally administered to female Sprague-Dawley rats for 4 and 8 weeks, respectively, and the influence of these treatments on the nerve tissue was examined hisologically and ultrastructurally. Abnormal gait was observed in the high dose group at the 4th week of treatment, but no neurological signs could be detected in the low dose group during 8 weeks of treatment. In the histopathological examination, the brain of animals belonging to the high dose group showed edema and necrosis in the thalamus and vacuolation in the oerebellar and vestibular nuclei. Small foci of hemorrhage were rarely observed in the thalamus. In the low dose group, the histopathological changes were characterized by axonal swelling in the cerebellar white matter, fasciculus gracilis of the cervical cord, and peripheral nerves. The swollen axons contained numerous neurofilaments with disorganized arrangement. Edema and necrosis in the thalamus or vacuolar change in the cerebellar and vestibular nuclei were not detected in the low dose group. These results indicated that the abnormal gait in the high dose group could be ascribed to the changes in the thalamus or in the cerebellar and vestibular nuclei.
