Figure 4.
Different magnitudes of the AFM indentation force generated different calcium responses in the bone cell network. The tested samples at each force level were separated into three groups based on their calcium responses. “No response” refers to mechanically stimulated cells that had no observed [Ca2+]i response. ‘Response but no propagation’ refers to mechanically stimulated cell showed [Ca2+]i transients, but all the other cells have no responses. ‘Response and propagation’ indicates that both the stimulated cell and the neighboring cells in the network displayed [Ca2+]i waves. The sample numbers for the indentation forces of 30, 60 and 90 nN are 6, 13 and 40, respectively.