Irradiation and responsiveness to pain stimuli in rats.

This study evaluates whether irradiation inhibits responses to pain in an animal model. We found that irradiation with doses of 10 Gy, 15 Gy and 17.5 Gy of the lumbar enlargement of the spinal cord inhibits the behavioural responses to the stimulus of the hot-plate. These doses were otherwise without effects. This data is discussed in view of the effects of irradiation of living cells, and we propose that a modification of pain signal processing is accomplished. Similar considerations apply to the human condition.