Effect of ionizing radiation on the nucleus supraopticus

In the structures of the nucleus supraopticus, changes of the activity of some enzymes (alkaline phosphatase, acid phosphatase, thiamine pyrophosphatase, butyrylcholinesterase, succinate dehydrogenase, glycerol-3-phosphate dehydrogenase) were studied in rat brains exposed to high supralethal doses of gamma radiation at early time interval after irradiation. The activity of alkaline phosphatase, acetylcholinesterase and butyrylcholinesterase increased in the wall of blood capillaries after irradiation with 50, 150, 500 Gy. The dose of 500 Gy induced the most pronounced activity. These membrane enzymes are highly sensitive to ionizing radiation. The activity of acid phosphatase, acid nonspecific esterase and thiamine pyrophosphatase increased in magnocellular neurons after irradiation with all doses of gamma radiation. Glycerol-3-phosphate dehydrogenase and succinate dehydrogenase showed a decreased activity in neurons, neuropil and capillaries.