Fig. 7. The upper two panels show a mitotic anaphase figure in two different planes
of focus with an asymmetric distribution of grains (same labelling and
analysis as in Fig. 6). The
middle two panels (arrows) show LRCs undergoing apoptosis 4.5 hours after a
dose of 1 Gy 
rays delivered 16 days after the post-irradiation
regeneration labelling protocol described for
Fig. 6. The true morphlogical
features of apoptosis in these autoradiographs are difficult to photograph and
can only be determined by careful optical focusing. The next lower two panels
and their different focal plane inserts (bottom panels) show a label-retaining
nucleus undergoing DNA synthesis, which is labelled with BrdUrd (left hand
panel), and a LRC undergoing mitosis (lower panel right), indicating that the
LRCs do indeed progress through the cell cycle and divide (see also data in
Table 1). (The same protocol
was followed as in Fig. 6.)
