Repair of sublethal radiation injury after multiple small doses in mouse kidney: an estimate of flexure dose

Journal Article · Fri May 01 00:00:00 EDT 1987 · Int. J. Radiat. Oncol., Biol. Phys.; (United States)

DOI:https://doi.org/10.1016/0360-3016(87)90297-5· OSTI ID:6273200

Stewart, F A; Oussoren, Y; Luts, A; Begg, A C; Dewit, L; Lebesque, J; Bartelink, H

Functional kidney damage in mice was measured after a series of fractionated X-irradiations. Doses per fraction of 0.75-12.5 Gy were given as 2, 5, 10, 30, 40, 60, or 80 equal doses in a total treatment time of 4 weeks. Renal function (measured by clearance of /sup 51/CrEDTA or hematocrit levels) deteriorated progressively, in a dose related manner, from 20 to 46 weeks after the start of treatment. The changes in renal function versus time were fitted by a polynomial regression through all data and interpolated values for /sup 51/CrEDTA clearance were then calculated at 30 and 40 weeks after treatment. Steep dose response curves were obtained and these were used to calculate isoeffective doses for the different fractionation schedules. There was a marked increase in total isoeffective doses from 2-30 fractions and these data were well described by a linear quadratic (L.Q.) expression for damage with an alpha/beta ratio of 2.3 +/- 0.2 Gy. There was only a slight increase in the total isoeffect dose as the size of the dose per fraction was decreased below 2 Gy and the measured isoeffect doses after 40 to 80 fractions were lower than predicted on the basis of an L.Q. model assuming complete repair between successive irradiations. The flexure dose for mouse kidneys irradiated 3 times per day was, effectively, 1 to 2 Gy and hyperfractionation using lower doses per fraction did not lead to significant, additional repair.

• Research Organization: Netherlands Cancer Institute, Antoni van Leeuwenhoekhuis, Amsterdam
• OSTI ID: 6273200
• Journal Information: Int. J. Radiat. Oncol., Biol. Phys.; (United States), Vol. 5
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
KIDNEYS
BIOLOGICAL FUNCTIONS
BIOLOGICAL RADIATION EFFECTS
RADIATION INJURIES
BIOLOGICAL REPAIR
CHROMIUM 51
DOSE-RESPONSE RELATIONSHIPS
EDTA
FRACTIONATED IRRADIATION
ISODOSE CURVES
MICE
X RADIATION
AMINO ACIDS
ANIMALS
BETA DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BIOLOGICAL RECOVERY
BODY
CARBOXYLIC ACIDS
CHELATING AGENTS
CHROMIUM ISOTOPES
ELECTROMAGNETIC RADIATION
ELECTRON CAPTURE RADIOISOTOPES
EVEN-ODD NUCLEI
FUNCTIONS
INJURIES
INTERMEDIATE MASS NUCLEI
IONIZING RADIATIONS
IRRADIATION
ISOTOPES
MAMMALS
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
RADIATION EFFECTS
RADIATIONS
RADIOISOTOPES
RECOVERY
REPAIR
RODENTS
VERTEBRATES
560152* - Radiation Effects on Animals- Animals