Figure 2.

Requirement for extracellular Ca²⁺ for suppression of apoptosis by A23187 and TG but not for suppression by IL-6, IFN-γ, TPCK, or BHA. M1-t-p53 cells were cultured at 32°C for 23 hr in DMEM without or with 2 mM EGTA (Upper) or in calcium-free DMEM (Lower). The concentrations of the compounds added were 500 nM A23187, 10 nM TG, IL-6 (10 ng/ml), IFN-γ (2 ng/ml), 1 μM TPCK, or 100 μM BHA.