Radioprotective effect of hypoxic hypoxia (8% O2) for different morphological elements of mouse kidney

The evaluation of the radioprotective effect of the air and nitrogen breathing mixture (8% O2) for different morphological elements of the mouse kidney is given. The kidneys are subjected to the single-time roentgen irradiation with the doses of 11-10 Gy and five-time fractionated irradiation with the total doses of 25-40 Gy. It is established by the morphometric study since 8 and 10 month after irradiation, that by the damage severity indices the dose modification factor (DMF) of the hypoxia constitutes 1.25-1.29; the hypoxia, protected the kidneys tubular apparatus with the DMF of 1.28-1.37; by the criterium of reducing the degree of replacement of the cortical substance parenchyma through the connecting tissues the DMF is equal to 1.32-1.37 by the single-time and 1.47-1.49 by the fractionated irradiation. The hypoxia radioprotective effect for arterial lesions appeared to be lower: 1.13-1.15 by the single-time and 1.16-1.18 - by the fractionated irradiation. Since by the kidneys functional indices the hypoxia DMF is equal to 1.25-1.35, the conclusion is made, that the arterial lesions damage is only a subordinate component of developing remote radiation pathology by irradiation. Application of hypoxic breathing mixture of the given composition makes it possible to increase the radiation dose by radiation therapy by 20-30% in the case, when the kidneys are the critical organ