Evidence for progesterone receptors in human osteoblast-like cells

We report on the presence of progesterone receptor and its mRNA in a human osteoblast-like cell line (HOS TE85) using recombinant DNA methods, saturation analysis, specific immunoprecipitation with an anti-progesterone receptor antibody, and Northern blot analysis. These osteoblast-like cells were also found to be responsive to progesterone in a dose-dependent fashion through an augmentation in cellular alkaline phosphatase activity. These results support the presence of progesterone receptors in bone cells and suggest a direct effort of progesterone and/or antiprogestins on osteoblast cell function.