Figure 9. A local and eventless rise of the prolonged Ca²⁺ transient.

Selected images of cytoplasmic rhod-2 fluorescence following the exchange of standard internal bathing solution for low [Mg²⁺]_cyto solution bathing a mouse skinned fibre. A gradual increase of Ca²⁺ over seconds (images marked 84–91 s) occurs locally without any obvious discrete events. At the imaged marked 93 s the locally increased cytoplasmic Ca²⁺ began to spread as an apparent Ca²⁺ wave.