Figure 8.

Ba²⁺ influx in CK1.4 cells pretreated with Tg, ionomycin or both. Aliquots (0.3 ml) of CK1.4 cells were loaded with fura-2 in the presence of 0.4 mM ouabain, washed, and preincubated for 1 min in 0.1 ml of Na-PSS + 0.3 mM EGTA containing either 200 nM Tg, 10 μM ionomycin, both Tg and ionomycin, or neither agent (control). The cells were then centrifuged, resuspended in 0.3 ml of Na-PSS + 0.3 mM EGTA + 1% BSA and incubated for an additional 1 min. After an additional centrifugation, the cells were resuspended in Li-PSS + 0.3 mM EGTA in the cuvette; BaCl₂ (1 mM) was added as indicated (n = 3).