Thymus repair compared with hemopoiesis repair in spleen after protracted irradiation.

Mature female mice of ICR strain were irradiated from the source 60Co with a daily dose rate of 5 Gy till total accumulated dose of 10 Gy for 2 days. Animals were examined in various intervals within 42 days after irradiation. The results obtained that protracted irradiation will induce a massive injury to hemopoiesis. The first repair processes occurred in thymus and were characterized by two phases. The first repair wave peaked about the day 10 and the second about the day 30 after irradiation. The repair processes observed in the red pulp of the spleen reached their highest intensity approximately between the days 14-16 after irradiation.