This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Ovarectomy and subsequent hormonal alterations can change bone homeostasis in affected individuals. A small cohort of 8 animals that were ovarectomized in 1998 and 1999 are being held for subsequent experimentation. The experimental design has not yet been develpoed.