Morphology of ON and OB following X-ray irradiation. A,C,E, Photomicrographs of olfactory turbinates (including the OB and ON) labelled with the βIIITubulin monoclonal antibody. A, In the control animals at low magnification, the axon bundles were labelled positively with βIIITubulin (open arrow) and positively labelled nerve fibres were seen surrounding the olfactory bulbs (black arrows). C, 24 hours post-irradiation axon bundles remained βIIITubulin-positive (open arrow) and βIIITubulin-positive nerve fibres (black arrows) were seen linking the ON with the OB which is the same as at 5 weeks post-irradiation (E). B,D,F, Photomicrographs of the ON at higher magnification labelled with βIIITubulin. B, The cell soma of OSNs, their processes, cilia and axon bundles were βIIITubulin-positive in the control mice. D,F, 24 hours and 5 weeks post-irradiation the distribution of βIIITubulin was the same as in the control mice. The dashed line in B,D,F represents the basal lamina. AB, axon bundle. (n=3 mice per group). * indicates septum.