Damage and repair of peripheral blood elements in rats following chronic irradiation at a dose rate of 574 mGy/day

Changes are described in the peripheral blood count of rats following chronic irradiation over a period of 30 days with a daily dose of 574 mGy (total dose 17.22 Gy) to day 180 after irradiation. Lymphocytes dropped after 24 hours of irradiation to 50% and to 10% after 30 days. Between days 7 and 30 after irradiation they remained at below 50% but to the 60th day they returned to normal values. In neutrophil segments an increase was observed at the 1st day of irradiation, between the 3rd and 14th day normal values, then a decrease up to the 30th day. Their return to standard values occurred to the 14th day. It may thus be stated that the decrease in total leukocytes is basically to the detriment of lymphocytes. A decrease in thrombocytes was found at the 30th day after irradiation. In the period of repair their values remained at above 60% between days 7-30 and at the 60th day they returned to control values. The values of erythrocytes were reduced between the 25th and the 30th days of irradiation to 85 to 90% and to day 60 after irradiation they reached the standard level. Changes in the reticulocyte count adapted to the needs of erythrocyte replacement. (author)