Fig. 7. The role of intracellular free Ca²⁺ in E-lam formation. (A) The spread cells were loaded with fura-2, and the ratio of 346/380 nm excitation indicating the level of intracellular free Ca²⁺ was measured by fluorimetry. Stable baseline Ca²⁺ was obtained for 50 seconds before the addition of staurosporine. A typical response is shown. (B) To study the role of intracellular free Ca²⁺, the spread cells were treated with Ca²⁺ chelators 2 mM EGTA or BAPTA-AM (0-10 µM) in presence or in absence of staurosporine and analyzed for cell spreading and E-lam formation. The results show the mean±s.d. of a typical experiment (n=8). (*P<0.05; ^**P<0.01; ^***P<0.001.)