Figure 4.

Modulation of store-operated Ca entry (SOCE) by ET-1 and 2-APB. SOCE was induced by using cyclopiazonic acid (CPA) and low external Ca²⁺. The addition timing of extracellular Ca²⁺ change is indicated in the top panels. (A) The effect of ET-1 on SOCE induced by 10 μM CPA with 15 min incubation in Ca²⁺ free Tyrode's solution. (B) The effect of ET-1 on SOCE induced by 20 μM CPA with 30 min incubation in Ca²⁺ free Tyrode's solution. (C) The effect of 40 μM 2-APB on SOCE. 2-APB was added in the same time of reintroduction of extracellular Ca²⁺ after perfusion of Ca²⁺ free Tyrode's Solution containing 10 μM CPA. (D) The effect of 40 μM 2-APB on SOCE. 2-APB was added into the Ca²⁺ free Tyrode's solution with 10 μM CPA during the 15 min incubation period. The gray traces represent controls; the black traces represent the treatments with ET-1 (A,B) or 2-APB (C,D), respectively.