Male osteoblasts respond more robustly to 1α,25(OH)
than females, an effect enhanced on microstructured titanium (Ti). Osteoblasts isolated from calvaria of male and female rats were plated on Ti surfaces. At confluence, cells were treated with 1α,25(OH)2D3 for 24 hours. Levels of osteoprotegerin (A, B) and latent tissue culture polystyrene (TCPS)-β1 (C, D) were measured in the conditioned media. *P < 0.05, Ti surfaces versus TCPS; #P < 0.05, 1α,25(OH)2D3 versus control; · P < 0.05, 10-9M 1α,25(OH)2D3 versus 10-8M.