Fig. 6.

Role of NFAT in mediating the effects of acidosis on osteoclastic resorption. Rabbit osteoclasts were plated on dentin slices and treated with calcitonin (10 μM) or cyclosporin A (CsA, 1 μM) for 30 min at pH 7.6. In some samples, the pH was then altered to 7.0 by increasing the partial pressure of CO₂ (respiratory acidosis). Experiments were stopped at 24 h, and the number of osteoclasts was assessed. The mean number of osteoclasts per slice was 170 ± 9, and no significant differences were observed among conditions. (A) Phase-contrast micrograph of resorption pits. (B) Quantification of the total area resorbed per slice. Data are means ± SEM, for three independent experiments, each performed in triplicate. Differences were assessed by using Student's t test. *, Significant difference for the effect of acidosis; #, significant difference for the effects of calcitonin or CsA, compared with untreated samples at the same pH.