Hypothermic and active (normothermic) golden and albino hamsters were given whole-body exposures to ionizing radiation with a60 Co irradiator. Hypothermia to body temperature ca. 7°C was induced using a helox-cold technique (80% helium, 20% oxygen, and 0°C ambient temperature). The radiation doses ranged from 600 to 5000 rads. Increased radioresistance was evident in the metabolically depressed hypothermic hamsters. Over a range of exposures up to 2000 rads, hypothermic hamsters showed increased mean survival times. Percent survival data for each type of hamster gave respective|${\rm LD}_{50(90)}$| values of 1067 ± 24 and 875 ± 15 for hypothermic and active golden hamsters, and 1143 ± 99 and 867 ± 34 for hypothermic and active albino hamsters. Dose-reduction factors were approximately 1.22 and 1.31. The increased radioresistance was examined in light of limited hypoxia and general metabolic depression.

This content is only available as a PDF.