Fig. 4. Time-lapse confocal fluorescence microscopy of GFP-actin in CCH-stimulated lacrimal acini reveals considerable actin remodeling. Confocal fluorescence microscopy images of rabbit lacrimal acini transduced to express GFP-actin were exposed to 100 µM CCH at the onset of the time-lapse sequence. Selected images of GFP-actin fluorescence at intervals throughout the time-lapse sequence are shown. (A) The same acinus shown in Fig. 3C immediately after CCH. Boxed image at 298 seconds is magnified and shown on the bottom row as GFP-actin, DIC and as an overlaid image. (B) Another CCH-stimulated acinus. Arrowheads, actin-coated structures; arrows, basolateral actin filament `bubbling'; barbed arrows, regions of apical actin filament thinning. Bars, 5 µm.