Figure 6. Functional activities of BMSCs, osteoblasts and osteocytes in aged rats compared to young rats. (A) Comparison of osteogenic and adipogenic differentiation ability of BMSCs between aged rats and young rats. BMSCs were cultured in osteogenic induction medium for 21 days, and alizarin red staining was performed. BMSCs were stained with oil red O after 14 days of culture in adipogenic induction medium, and the red drops in the figure were lipid droplets; (B) Determination of bone formation protein and statistics of protein relative expression in osteoblasts of aged rats and young rats