Quantitation of intracellular Ca²⁺ changes in sensitive and resistant cells.

Cells were treated with diluent alone (solid line) or 1 μM CdA (dotted line) for 30 minutes. Five minutes into the incubation, 1 μM Indo-1 AM was added to the culture dishes. At the end of the incubation, cells were washed with and then resuspended in Ca²⁺-free PBS and read on a Becton Dickinson FACS Vantage using a UV laser. Histograms depict Indo-1 fluorescence, which indicates intracellular Ca²⁺ levels.