title: Effect of medium pH on osteoclast activity and osteoclast formation in cultures of dispersed rabbit osteoclasts.
abstract: We investigated the effect of medium pH on activity of isolated osteoclasts and have also looked at the possibility that medium pH affects osteoclast numbers during culture. Osteoclast-containing cell suspensions prepared from neonatal rabbits were cultured on bovine bone slices at pH 6.5, 7.0, or 7.5. After 24 or 48 h of culture, the cells and bone slices were fixed and stained for tartrate-resistant acid phosphatase (TRAP). After counting the osteoclasts, the cells were removed and the resorption lacunae stained by immunostaining using anticollagen type I antibody and then quantitated. We found that the resorptive activity of isolated rabbit osteoclasts was sharply increased at pH 6.5-7. Osteoclast differentiation and proliferation, on the other hand, were optimal at pH 7.0-7.5 but decreased at pH 6.5. The results thus imply that pH regulation of the bone surface environment can dramatically alter both the number of osteoclasts and their resorptive activity.
authors.affiliation: MRC Group in Periodontal Physiology, Faculty of Dentistry, University of Toronto, Ontario, Canada.
authors.forename: T
authors.initials: T
authors.lastname: Shibutani
authors.forename: J N
authors.initials: JN
authors.lastname: Heersche
mesh_terms: D000818:Animals; D001862:Bone Resorption; D002452:Cell Count; D002454:Cell Differentiation; D002478:Cells, Cultured; D006863:Hydrogen-Ion Concentration; D010010:Osteoclasts / Q000737:chemistry / Q000166:cytology / Q000378:metabolism*; D011817:Rabbits; D013194:Staining and Labeling