Effect of ionizing radiation on total protein-bound neutral hexoses in the plasma of mice.

Total protein-bound carbohydrates (PBC), as neutral hexoses, were quantified in the plasma of C3H mice as a function of time relative to whole-body exposure to either monoenergetic 14-MeV neutrons or mixed gamma-neutron radiations delivered at a rate of approximately 20 rads/ min. The reported doses, 365 to 530 rads, were those which yielded survivors under the stress of daily bleeding. A striking difference was observed between those radiosensitive animals which died after exposure and the more resistant individuals which, although exposed to identical doses, survived the observation period. In the former population, the PBC concentration rose to high values and remained elevated until the death of the animal. By contrast, the survivors showed little change in PBC, deviating only slightly from their preirradiation base-line values. The mean preirradiation PBC concentration in the mice which survived 30 days, while statistically significant (p < 0.01) only at the lowest reported dose, was consistently lower than that of those which died during the same period. The magnitude of the difference was inversely related to the radiation dose. The refinement of these data to provide an index to radiosensitivity prior to and prognosis after irradiation in otherwise healthy individuals is proposed.