title: Fluoride inhibition of bone mineralization may depend on physical/chemical properties.
abstract: The properties of fluoride (F) incorporation into bone powder in vitro were studied in an attempt to clarify possible mechanism for F inhibition of bone mineralization and soft tissue mineral deposition in vivo. Rat bone powder was prepared with minimal physical and chemical stress, and exposed to F (less than 1 mmol) in aqueous solutions buffered to pH 7.4. Initial experiments confirmed reported data that the rates of F incorporation into bone mineral in vitro resemble F clearance from blood in vivo. The rate of F incorporation was inversely proportional to the amount of F added to supernatants and decreased exponentially with time. Following F incorporation, the bone mineral became less soluble, with solubility inversely proportional to bone F concentration. However, a fraction (about 20%) of F freshly incorporated in bone powder dissolved readily in pH 7.4 buffer and appears to be adsorbed F. The fraction of incorporated F that was readily dissolved decreased with time over the initial 24 h after incorporation, was proportional to the amount of F freshly incorporated, and was associated with an inhibition of further F incorporation.
authors.affiliation: Department of Medicine, University of Toronto, Canada.
authors.forename: J E
authors.initials: JE
authors.lastname: Harrison
authors.forename: A J
authors.initials: AJ
authors.lastname: Hitchman
authors.forename: A
authors.initials: A
authors.lastname: Hitchman
authors.forename: S A
authors.initials: SA
authors.lastname: Hasany
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000187:drug effects / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D005459:Fluorides / Q000378:metabolism; D007700:Kinetics; D008657:Metabolic Clearance Rate; D008903:Minerals / Q000378:metabolism*; D051381:Rats; D012969:Sodium Fluoride / Q000378:metabolism / Q000493:pharmacokinetics / Q000494:pharmacology*
chemical_list: D008903:Minerals; D012969:Sodium Fluoride; D005459:Fluorides; D002118:Calcium