4.2. Bone Cell and Vasculature Labeling

Calcein AM (Ebioscience, USA; 20 mg/kg, S.C.) was injected 3 days before examination to track the live osteocytes [25]; and five min before imaging. Dextran (dextran, Texas Red, 70 kDa, Thermo Fisher Scientific., Waltham, MA, USA; 12.5 mg/kg) was systemically administered to visualize the vasculature and blood flow in the bone.

To further characterize the damaged cells due to impaired blood supply, 100 μL of a solution of propidium iodide (PI, Sigma-Aldrich, USA; 1 mg/mL) was intravenously injected into the animal to label the dead cells.