FIGURE 6.
Domain-specific function of CSR in SMIE cells. A, representative images (Confocal on live cells; X-Z sections) of Fluo-4-loaded polarized SMIE cells on Transwell filter. Average intensity data of the demarked (equal) region of interest (dashed boxes) in the apical (white) and basal (yellow) were plotted showing changes in Fluo-4 ([Ca2+]i) signal. Graphical presentation of (mean fluorescence traces) of Fluo-4-loaded SMIE cells represents [Ca2+]i rise within the apical/basal region. All applications were made apically. B, addition of l-Phe (10 mm) and 0.5 mm external Ca2+. C, [Ca2+]i rise due to application of 1.2 mm external Ca2+. Inset, bar diagram showing the rate of increase in apical [Ca2+]i signal (p < 0.01) than basal signal in response to [Ca2+]o, indicating the induction of Ca2+ mobilization from apical to basal region. D, effect of l-Phe in the presence of CSR antagonist (NPS-2143; 1 μm) and thapsigargin (Tg; 1 μm). E, simultaneous changes in Fluo-4 fluorescence in apical and basal regions of the cells following application of thapsigargin (1 μm).