The effect of substrate composition and condition on resorption by isolated osteoclasts.
Osteoclasts isolated from 10-day-old rabbits were studied in a cell culture system to obtain further insight into the possible mechanisms involved in the process of bone resorption. Osteoclasts were cultured on the surfaces of devitalized mammalian bones, a composite of polycrystalline synthetic hydroxyapatite and geological single crystal hydroxyapatite. The structural interaction of osteoclasts with these various substrates was morphologically characterized by using a scanning electron microscope. Viable osteoclasts were observed to adhere and extend pseudopodia and filopodia for all cases of calcium-phosphate surfaces. However, actual resorbing process was only observed in devitalized bone surfaces. Resorption pits of various sizes were found in multiple series and showed a preference for mineral-exposed area over collagen-exposed area. The difference observed between resorption of those areas of bone surface and the failure of osteoclasts to resorb non-tissue substrates are discussed in relation to current theories of the mechanisms of mineral dissolution and resorption in mammalian calcified tissues.
Shimizu
H
H
Department of Oral Biology, Harvard School of Dental Medicine, Boston, MA 02115.
Sakamoto
S
S
Sakamoto
M
M
Lee
D D
DD
D000818:Animals; D001862:Bone Resorption; D002478:Cells, Cultured; D003470:Culture Media; D005260:Female; D006882:Hydroxyapatites; D008252:Macaca fascicularis; D008855:Microscopy, Electron, Scanning; D010010:Osteoclasts / Q000502:physiology*; D011817:Rabbits
D003470:Culture Media; D006882:Hydroxyapatites