Figure 1.
Extracellular calcium regulates velocity and turning in the absence of chemoattractant. Cells were analyzed in a Sykes-Moore perfusion chamber. All test solutions were made in tricine buffer (TB) which contained 5 mM K+, pH 7.0. Test solutions tested were tricine buffer plus 5 mM EGTA (EGTA), or tricine buffer containing 0 to 40 mM CaCl2. Error bars represent the standard deviation of the means. At least 10 cells were analyzed in each of three independent experiments and the data pooled.