A bone marrow peroxidation study on low-dose irradiated rats

The aim of this work was to study the modification of some biochemical parameters induced in animals irradiated by in vivo contamination with tritiated water (HTO). Four groups of animals were chronically irradiated by ingestion over 145 d. Irradiation doses were, respectively, 4, 9, 27, and 49 cGy. Another group was a control (nonirradiated) group. We followed the peroxidation level in bone marrow tissue using the thiobarbituric acid test, and results are expressed by malondialdehyde (MDA) concentration (mol MDA/mg protein). We adapted known methods to the study of a very small amount of tissue. We also followed the variation of deoxyribonucleic acid (DNA) concentration (mol/mg protein) in the tissue. The studied parameters seem to be influenced by irradiation, but not necessarily in a monotonous way with respect to irradiation dose. The peroxide level reported to mg protein is modified in a statistically significant way only for the highest dose. DNA content was found to decrease for irradiated rats starting with the lowest dose, and the peroxide level reported for DNA content increased for irradiated animals.