The effect of steroids on experimental brain edema induced by irradiation

In order to study the effect of steroids on brain edema, complicated by radiotherapy to brain tumors, an experiment was carried out in rats. Five thousand rads of cobalt-60 were irradiated to the head only of a rat, and 20 mg/kg of water-soluble prednine was given intraperitoneally. A single administration of the whole dose increased the amount of brain fluid to 79.35 +- 0.30 g/ 100 g wet wt.. This value was not significantly different from that of the rat which had received only the 5,000 rad irradiation. In a rat which received prednine in 6 divided doses at intervals of 4 hours, the fluid amount reached 78.33 +- 0.52 g/ 100 g wet wt. and was clearly lower than that of the rat which had been irradiated only, 79.51 +- 0.23 g/ 100 g wet wt. neither was the value significantly different from that of a normal rat which had not been exposed 78.72 +- 0.82 g/ 100 g wet wt.. Therefore, fractional administration of prednine was demonstrated to be effective. (Kanao, N.)