Figure 1.

Characterization of SOCE and I_CRAC in synthetic VSMCs. A) Thapsigargin (TG) (2 μM) activates SOCE in synthetic VSMCs that is sensitive to 5 μM Gd³⁺ (n=72). B, C) Similar inhibition of SOCE was achieved with 50 μM 2-APB (B) (n=49) and 50 μM ML-9 (C) (n=26). D) Store depletion by dialysis of 20 mM BAPTA activates a relatively small current in 10 mM Ca²⁺. E) I/V relation of current shown in D before and after subtraction of the sweep right after break-in. F) Representative data of I/V relations of DVF current before and after subtraction of Gd³⁺-insensitive current. G) Store depletion by dialysis of 20 mM BAPTA in synthetic VSMC activates I_CRAC-like currents, revealed in DVF solutions that were inhibited by 5 μM Gd³⁺; sweeps represented are indicated by differently shaded asterisks. H) I/V relations in Ca²⁺-containing solution (10 mM), before and after Gd³⁺ addition. I) Statistical analysis of monovalent I_CRAC inhibition by 5 μM Gd³⁺, normalized to control. J, K) Similar results to those in G, H were obtained with the A7r5 smooth muscle cell line. L) Statistical analysis of monovalent I_CRAC inhibition by 5 μM Gd³⁺, shown as current densities. All Ca²⁺ imaging traces are average data from several cells analyzed simultaneously. Data are representative of 3 to 4 independent experiments.