Fig. 5. Mechanically induced calcium waves in HeLa and Cx-transfected HeLa cells are inhibited by desensitization of ATP receptors. Cell monolayers were loaded with fura-2 and single cells were mechanically stimulated before or 5 minutes after desensitization of P2 receptors by addition of 10 µM ATP. Numbers represent the number of cells to which the subsequent calcium wave propagated.