Accession Number:

AD0628791

Title:

RECOVERY FROM RADIATION INJURY IN DOGS AS EVALUATED BY THE SPLIT-DOSE TECHNIQUE,

Descriptive Note:

Corporate Author:

NAVAL RADIOLOGICAL DEFENSE LAB SAN FRANCISCO CALIF

Personal Author(s):

Report Date:

1965-12-30

Pagination or Media Count:

28.0

Abstract:

The split-dose technique was used to evaluate recovery from radiation injury in dogs given an initial conditioning exposure to 217 R, which is approximately 23 of the LD50. Based on LD50s determined at 1, 3, 7, 14, and 20 days after the conditioning exposure, recovery is rapid with 50 recovery occurring by about 3 days. Because of relatively large 95 confidence intervals, the recovery rate per se is difficult to establish. An exponential curve with a recovery half-time of 3.1 days may be an acceptable fit to the data. However, between 3 and 20 days the animals radiosensitivity appeared to change linearily at a rate of approximately 8.5 Rday. At 20 days approximately 40 R of radioresistance was detected, but this was not statistically significant. The numbers of circulating leucocytes were followed for several months after exposure to 150 R or 217 R. The leucocyte counts return to only 70-80 of the pre-irradiation values by approximately 4 months. The data are discussed in terms of the proposed correlation between recovery from radiation injury and basal metabolic rate or changes in the number of circulating leukocytes. Author

Subject Categories:

  • Radiobiology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE