Figure 1.

Spatial pattern of [Ca²⁺]_i signaling in the ciliary bilayer. (A) Confocal microscopic image of an isolated ciliary bilayer loaded with the Ca²⁺-sensitive dye fluo-3. Individual cells are outlined in white. The PE (cuboidal) and NPE (columnar) cells whose responses are graphed in G are indicated by the white arrow and arrowhead, respectively. (Bar, 5 μm.) (B–F) Sequential pseudocolored images of the same preparation at 10, 13, 15, 17, and 19 s after stimulation with 100 μM epinephrine. Fluorescence intensity in this and subsequent confocal images and line scans is represented by the pseudocolor scale shown on the bottom. Note that the [Ca²⁺]_i increase begins in the PE, then spread to the NPE. (G) Fluorescence increase in the two cells indicated in A. Open and closed circles represent normalized fluorescence intensity (F/F₀) in the NPE and PE, respectively; each measured over a 1.7-μm² region. Tracing is typical of that seen in 12 separate experiments. The black bar indicates the period of the stimulation. (H) [Ca²⁺]_i signaling in the PE and NPE during stimulation with 100 μM phenylephrine. Tracing is typical of that seen in 15 separate experiments. (I) [Ca²⁺]_i signaling in the PE and NPE during stimulation with 10 μM acetylcholine. Tracing is typical of that seen in 25 of 35 experiments.