Fig. 3.

PDE5A inhibitors tadalafil and vardenafil increase bone mass. (A) Areal BMD of the total skeleton and of L4-6 vertebrae and right femur and tibia in female mice treated with vehicle (gray), tadalafil (green), or vardenafil (blue) measured at 0, 2, 4, and 6 wk by a PIXimus small animal densitometer (details and doses in Methods). (B) Representative images of 3D reconstructions of L5 vertebral trabecular bone at 6 wk following vehicle or drug treatment. Static quantitative morphometry from μ-CT, providing measures of vBMD, BV/TV, Tb.N, Tb.Th, Tb.Sp, and connectivity density (Conn.D). Data are shown as mean percent change ± SEM (vs. vehicle). Statistics: two-tailed Student’s t test; *P < 0.05, **P < 0.01, or as shown vs. vehicle; n = 4 to 5 mice per group.