Figure 3. Regions of osteoclastic activity with age.

Enlarged at 40X from encircled areas in Figure 1, TRAP localization is demonstrated across all age groups in a) coronal and b) apical regions. In young rats, resorption activity is represented by robust multinucleated pits (red staining) surrounded by several dark purple nuclei. In older rats mononucleated pits predominated with decreased intensity of red stain. Scale bar = 150 µm. Results show osteoclastic activity declined with increasing age in c) distal regions and d) increased in mesial regions.