Podosome expression in osteoclasts: influence of high extracellular calcium concentration.

: In this study the effect of high extracellular calcium concentration has been evaluated, by immunofluorescence, on podosome expression in chicken osteoclasts. Cells were cultured in presence of 0.2 and 4 mM calcium for 90 minutes and microfilaments were detected, after fixation and permeabilization, by decoration with rodhamine conjugated phalloidin. Results showed that increased extracellular calcium concentration induces the inhibition of podosome expression indicating that these close-contact areas are capable of calcium-mediated regulation.