Figure 4.

Influence of irradiation on the stem cell population as shown by BrdU-incorporation in M. lignano. (A) Confocal projection of labeled S-phase cells in non treated control animal after 30 minutes BrdU-pulse. Note bilaterial distribution of BrdU cells and clusters in testes (t) and ovaries (o). (B) Confocal projection of labeled S-phase cells after one week recovering from 80 Gy irradiation. BrdU labeled cells can be found only in gonads. (C) Confocal projection after 3 weeks recovering from irradiation, BrdU incorporation was comparable with control. (D) Effect of irradiation on mitoses. Note the dramatic reduction in the number of mitoses 3 hours and 1 day postirradiation and the recovery of cell proliferation after 7 and 21 days. scalebar 100 μm.