Figure 2.

Dynamic organ-level distribution of Radium-223 evaluated in skeletally mature male CD-1 mice. Mice (n = 4–5 per group) were killed at one, four, and 24 hours postinjection, and organs evaluated for activity by γ counting. A) The distribution is expressed in percent injected activity (%IA ± SD) representing the amount in each organ relative to the administered dose and (B) normalized to the weight of each organ (%IA/g ± standard error of the mean). C) ²²³Ra clearance profile was defined measuring whole-body radioactive content over 24 hours. D-F) To confirm ex vivo γ count results, whole-body undecalcified cryosections (14 µm) were obtained at 24 hours after administration. Autoradiography revealed skeletal uptake in the calvaria and vertebrae, while soft tissue accumulation is recapitulated in the spleen and kidney. Scale bars = 1cm.