Accession Number : AD0680611

Title :   EARLY INCREASE IN THE MISCIBLE DEOXYCYTIDINE POOL IN RATS AFTER X IRRADIATION,

Corporate Author : NAVAL RADIOLOGICAL DEFENSE LAB SAN FRANCISCO CALIF

Personal Author(s) : Guri,Charles D. ; Minot,Henry J. ; Swingle,Karl F.

Report Date : 22 NOV 1968

Pagination or Media Count : 20

Abstract : Intraperitoneal and intravenous injections of tracer quantities of 3H- or 14C-labeled deoxycytidine (CdR) were used to investigate the biologic half-life, the miscible pool size, and the turnover rate of CdR in normal and X-irradiated rats. The specific activity of highly purified CdR isolated from blood plasma samples taken at various times after injection of the tracer CdR was used as the basis for calculating these values. The mean values observed for normal rats were: biologic half-life 116 minutes, miscible pool 790 micro g/rat (100 to 180 g), and turnover rate 7.0 mg/24 hours/rat. The miscible pool of CdR appeared to be non-uniform, with the intracellular concentration appreciable higher than the general body-water concentration. About one-third of the total miscible CdR appeared to be intracellular. After relatively low doses of whole-body X-irradiation (25 to 100 rads), there were alterations in the turnover kinetics of CdR, but the presence of non-steady state made computation of the above three values impossible. However, the data are fully consistent with an increase in the miscible pool size of CdR, occurring as early as 1 hour postirradiation. The data do not provide information as to the mechanism for this apparent increase. (Author)

Descriptors :   (*WHOLE BODY IRRADIATION, RATS), (*PYRIMIDINES, METABOLISM), X RAYS, LABELED SUBSTANCES, HALF LIFE, BLOOD PLASMA, BLOOD CHEMISTRY, RADIATION EFFECTS

Subject Categories : Radiobiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE