fig5

Figure 5. Osteoclasts and blood Ca²⁺. Osteoclasts were counted from TRAP stained sections and serum TRACP 5b activity was measured at three time points (before inoculation of cells, days 17 and 24) as a systemic marker of osteoclast number. Blood Ca²⁺ was measured from terminal blood samples for detection of hypercalcemia. A: Representative images of the TRAP staining; B: statistically significant changes were not observed in the number of osteoclasts at tumor-bone interface; C: serum TRACP 5b was decreased in the ZOL group already on day 17 and in the ZOL and DOX + ZOL groups on day 24 compared to the control group; D: hypercalcemia was prevented in the ZOL and DOX + ZOL groups. Data are expressed as mean ± SD, n = 7-8 animals. Scale bars 50 μm, arrows osteoclasts. *Significantly different from control group (P < 0.05); ***significantly different from control group (P < 0.001); NS: non-significant; TRAP: tartrate resistant acid phosphatase; TRACP 5b: tartrate resistant acid phosphatase 5b; DOX: doxorubicin; ZOL: zoledronic acid