title: Time course of loss of residual radiation damage in murine skin assessed by retreatment.
abstract: The amount of radiation damage remaining in mouse foot skin has been assessed by retreatment from 10 days to 6 months after a range of first doses. The acute skin reaction was used as the endpoint. Mice hind feet were first irradiated with a range of single doses (15-37.5 Gy) covering zero to near full effect. Feet were retreated with a full range of single doses together with groups of non-previously treated age-matched control mice. No age-related changes in radiation sensitivity were observed. Dose-response curves were constructed for all retreatment times for each priming dose, and isoeffect doses were calculated for both peak and average skin reactions. If 2-6 months were allowed to elapse before retreatment, the skin could be reirradiated as if it were previously untreated. However, if only 1 month was allowed to pass before retreatment, damage was 'remembered' after all first doses. The amount of damage 'remembered' in terms of dose was 11 Gy after a first dose of 37.5 Gy, and was less after the lower first doses.
authors.affiliation: Department of Experimental Radiotherapy, University of Texas M.D. Anderson Cancer Center, Houston 77030.
authors.forename: N H
authors.initials: NH
authors.lastname: Terry
authors.forename: S L
authors.initials: SL
authors.lastname: Tucker
authors.forename: E L
authors.initials: EL
authors.lastname: Travis
mesh_terms: D000818:Animals; D004307:Dose-Response Relationship, Radiation; D005260:Female; D051379:Mice; D008809:Mice, Inbred C3H; D011833:Radiation Injuries, Experimental / Q000503:physiopathology; D012867:Skin / Q000503:physiopathology / Q000528:radiation effects*; D013997:Time Factors