Circadian Rhythmicity in the Sensitivity of Two Strains of Mice to Whole-Body Radiation

Abstract

When male mice of the Swiss-Webster and C(3)H strains are maintained on a light-dark cycle in which the light begins at 7 a.m. and ends at 7 p.m., they are more sensitive to whole body x-irradiation (800 to 900 roentgens) given at 2 a.m. than at any other time in the cycle tested.