Fig. 6.

Effect of photolytic release of inositol 1,4,5-trisphosphate (IP₃) from caged-IP₃ on Ca²⁺ signaling of airway SMCs. A: fluorescent images of part of an airway obtained by confocal microscopy showing the intracellular Ca²⁺ signaling of airway SMC before (left) and after (right) the UV flash. Dashed white oval represents the position and size of the zone of UV illumination. B: intracellular Ca²⁺ oscillatory waves induced by photolysis of caged-IP₃. When the flash time was extended from 0.5 to 1.5 s, the Ca²⁺ signaling increased from a single Ca²⁺ transient to multiple Ca²⁺ oscillations. F/F₀, fluorescence ratio.