Pseudocolored images of changes in intracellular free Ca2+ in AtT-20/D16v-F2 cells, monitored at 9 sec intervals with fluo-4, AM (F14201, F14202, F14217, F23917).
In order to induce an influx of Ca2+, the cells were depolarized with 50 mM KCl in frame 2 and exposed to 5 µM ionomycin (I24222, a Ca2+ ionophore) in frame 8. The images are pseudocolored according to fluorescence intensity, with red representing high Ca2+ concentrations and blue representing low Ca2+ concentrations. The images were acquired using a fluorescence microscope equipped with a longpass filter set appropriate for fluorescein and a Photometrics Quantix cooled CCD camera.
