Radiation-Induced Changes in the Nucleic Acids of Cerebellar Neurons

Abstract

The aimof research was to study radiation-induced changes in nucleic acids of cerebellar cortex neurons after exposure to small doses of ionizing radiation.Material and methods.The study included 150 male rats aged 4 months at the beginning of the experiment that were subjected to a single exposure of 60Co γ-rays dosage 0.1–1.0 Gy. Neuromorphological methods evaluated morphometric and tinctorial parameters of cerebellar neurons, as well as the dynamics of nucleic acids in neurons of the ganglion and granular layers of the cortex over the entire life span of animals. The results were statistically processed using Statistika 6.1 software, parametric criteria, mathematical modeling, and defining the potential for their development.Results.The animals of the control and experimental groups manifested wave-like changes in the content of nucleic acids in the cerebellar neurons throughout their life with a gradual decrease in parameters by the end of the post-radiation period. Moreover, DNA changes in the nuclei and RNA changes in the nucleoli were typically associated with changes in their size; however, changes in the cytoplasmic RNA were apparently associated with different physiological conditions of neurons (rest, excitation, inhibition). Regression analysis showed that irradiation in the studied doses had a nonlinear stochastic effect on neuro-morphological parameters, revealed no dose-time dependence and did not cause significant organic changes in cerebellar neurons. At the end of the postradiation period, with the death of animals in both – experimental and control groups, the content of nucleic acids in neurons statistically significantly decreased in all groups, and this process was more pronounced in the group of irradiated animals.Conclusion.No significant radiation-induced changes were detected in the content and topochemistry of the products of histochemical reactions with the detection of nucleic acids in the structures of neurons of the cerebellar cortex. However, at the end of the experiment, the content of nucleic acids in neurons in irradiated animals decreased more significantly than in animals of age control (p <0.05).