Problems of Radiation Medicine and Radiobiology

Fractionate effect of ionizing radiation and nitric oxide on tumor growth in rats

O. B. Ganzha, M. O. Druzhyna, L. I. Makovetska, O. O. Glavin, L. F. Klepets, V. M. Mikhailenko
R.E. Kavetskyy Institute of Experimental Pathology, Oncology and Radiobiology, NAS of Ukraine, 45,Vasilkovskaya str., Kyiv, 03022, Ukraine

Objective. To investigate the effect of ionizing radiation and nitrogen oxides on the growth and development of Guerin's carcinoma transplanted in rats.
Materials and methods. Studies have been conducted on white nonlinear male rats weighing 125–160 g. Animals were exposed of nitrogen oxides and/or ionizing radiation, and then were transplanted Guerin's carcinoma. The dynamics of tumor growth and changes of free radical processes in the blood system by biophysical and biochemical methods were investigated.
Results. It is shown that the effect of the studied environmental factors leads to disruption of oxidative processes in the animal's organism, which contributes to the growth and development of tumors.
Conclusion. Pre-exposure to low doses of ionizing radiation and/or exogenous nitrogen oxides significantly accelerates the growth of Guerin's carcinoma. This process is accompanied by a disturbance of oxidative metabolism and the development of oxidative stress.

Key words: ionizing radiation, nitrogen oxides, Guerin's carcinoma, free radical processes, the blood system.

Problems of radiation medicine and radiobiology. 2014;19:389-397.