Effects of Cobalt Radiation on the Rat Brain

3 Abstract: This invesrigation was carried out to follow up radiation induced changes in brain of Wistar rats. Rats (weighing 160 to 180 g) were randomly divided into 4 groups of 6 each. Three groups were irradiated with 5 y, 7.5 and 12 Gy. The fourth group served as normal control. Results demonstrated dosage dependent changes in different parts of the brain tissue. Histopathological studies of the central nervous system revealed radiation-induced lesions early after exposure with congestion and edema. Marked and irreversible changes included gliosis, necrosis of neurons and vacuoles which were more pronounced in the subcortical regions. It was concluded that radiation injury is associated with irreversible damage to the neural stem cell compartment and induced apoptosis and depletion of oligodendrocytes may cause vacuolation and demyelination in brain.