SYSTEMIC FACTOR IN RECOVERY OF RAT KIDNEY FROM X IRRADIATION:THYMIDINE-H3 INCORPORATION STUDIES

摘要

1. The effect of X irradiation on thymidine-H3 incorporation into kidney cells (thymidine index) was measured at 4-8 hour intervals up to 96 hours in unilaterally nephrectomized female weanling rats.n2. A sharp drop in the thymidine index occurred during the first l6 hours after the kidney only was irradiated with 1000 rad, and also after the kidney was irradiated with 125 rad or 500 radnat the same time the body received 500 rad. Irradiation of the body, but with the kidney completely shielded had no apparent inhibitory effect on kidney thymidine incorporation.n3. The ability of the irradiated kidney to incorporate thymidine reappeared in 24 hours if the remainder of the body was not irradiated. When both the body and the kidney were irradiated, recovery of thymidine uptake depended on the amount of radiation received by each.n4. An explanation for the above observations is offered on the basis of a postulated systemic factor, the formation or induction of which could be affected by radiation and which is essential for thymidine incorporation in the kidney.