Figure 4

TGF-β2 induces store-operated calcium entry (SOCE) in UMR106 cells. (A) Representative original tracings (left panel) showing intracellular Ca²⁺ concentrations ([Ca²⁺]_i) in Fura-2/AM-loaded UMR106 cells before and after removal of extracellular Ca²⁺, addition of the sarco-endoplasmic Ca²⁺-ATPase (SERCA) inhibitor thapsigargin (1 µM), and readdition of extracellular Ca²⁺ in the absence (open squares) and presence (closed squares) of TGF-β2 (10 ng/ml, 1 h). (B) Arithmetic means ± SEM (n = 124–173 cells measured on three different days) of the peak (left) and slope (right) values of [Ca²⁺]_i increase after addition of thapsigargin reflecting Ca²⁺ release from intracellular stores. (C) Arithmetic means ± SEM (n = 124–173 cells measured on three different days) of the peak (left) and slope (right) values of [Ca²⁺]_i increase following readdition of extracellular Ca²⁺ reflecting store-operated Ca²⁺ entry. White bars: without, black bars: with TGF-β2 (10 ng/ml, 1 h). ***p < 0.001 indicates significant difference (unpaired t-test).