[Gas exchange intensity: relation to the body radiation resistance]

In the absence of immobilization stress gas exchange in rats does not increase in response to exposure to 6 to 13 Gy. Oxygen uptake intensity by intact animals at room and low ambient temperature is a stable individual characteristic positively correlating with life span following acute bone marrow irradiation. It is hypothesized that high gas exchange in radioresistant animals is linked with high inherent DNA synthesis and reparation. In animals experiencing immobilization stress the correlation between gas exchange reactivity and body radioresistance is supposed to be a result of more intensive uptake of oxygen diffusing in cells and consequent reduction in nucleus oxygenation and mitigation of DNA radiation-induced damage.