ON THE PROBLEM OF THE AGE OF RATS USEDFOR ELECTRON PARAMAGNETIC RESONANCESPECTROSCOPY STUDIES

Abstract

Introduction: After irradiation for the rehabilitation of persons affected by uncontrolled radiation
exposure (from several days to several tens of years) for the purpose of reconstruct the absorbed doses
after a long time applies a method that based on electron paramagnetic resonance spectroscopy (EPR
– dosimetry). This method is a very effective tool for retrospective individual dosimetry, because it
makes possible to measure materials that are part of the human body [5, 6, 13, 14, 18, 20]. ESR
measures the quantity of stable radicals, created due to radiation exposure to tooth enamel.
Aim of research: Determination of the feasibility of conducting studies on the measurement of the
absorbed doses use rat’s enamel.
Materials and methods. The experimental study was carried out on 38 white laboratory rats of the
«Wistar» breed. The mammals were separated on 4 groups: I -
56MnO2, II - MnO2, III -
60Co and IV –
control, its weight were 220 – 330 gr.
The first two groups were beta-irradiated in the IVG.1M («Baikal») nuclear reactor, which is located
70 km from the city of Kurchatov. The group of third was gamma-irradiated in the Semey Oncology
Center. After the animals’ decapitation the biological materials (teeth) were delivered to the laboratory of
the Department of Applied Physics of the Okayama University of Science (Japan).
Standard parameters of EPR spectra measurements were used for the equipment (JEOL JESFA100).
Results: During the measurements it was shown that the samples of rats dental enamel showed no
presence of the EPR signal, after which it was determined that the age of enamel formation is insufficient
for such studies and requires more accurate and qualitative approach to the selection of the rats.