A Quantitative Technique for Measuring Renal Damage After Irradiation

An experimental system in the mouse was used to measure the effects of radiation on the kidney. After removal of the right kidney, the left kidney was allowed to hypertrophy, was localized through the skin, and was irradiated with 300 kVp x rays. Mice were observed for 18 months. Death began at 2 months after irradiation, reached a peak between 6 and 10 months after irradiation, but continued for up to 18 months. The major histological change was complete loss of the proximal and distal convoluted tubules. The LD50, calculated from data for 6 to 16 mo. after irradiation dropped from 2358 rads at 6 mo. to 1300 rads at 16 mo. With 10 fractions, the pattern of death was similar except that the LD50 at 8 mo. increased to 4709 rads. This study indicates that mouse kidney is extremely radiosensitive, renal damage accumulates for long periods of time, and significant recovery occurs with fractionation.