Agonist-induced Ca²⁺ response and impaired SOCE in sgk1^−/− and sgk1^+/+ platelets. (A) Representative tracings of Fura-2-fluorescence reflecting cytosolic Ca²⁺ concentration [Ca²⁺]_i of sgk1^+/+ (black line) and sgk1^−/− (gray line) platelets before and after stimulation with thrombin (0.02 U/mL), CVX (1 μg/mL), CRP (10 μg/mL), and ADP (10μM) in the absence (0.5mM EGTA, left) or presence (1mM Ca²⁺, right) of extracellular Ca²⁺. (B) Arithmetic mean of maximal Δ[Ca²⁺]_i ± SD (n = 4 per group). **P < .01. (C) Fura-2-fluorescence reflecting cytosolic Ca²⁺ concentration [Ca²⁺]_i of sgk1^+/+ (black line) and sgk1^−/− (gray line) platelets after exposure to 5μM thapsigargin in the nominal absence of extracellular Ca²⁺ for 10 minutes and subsequent addition of 1mM extracellular Ca²⁺. Representative tracings (left) and arithmetic mean (right) of maximal Δ[Ca²⁺]_i ± SD (n = 6 per group) before and after addition of 1mM Ca²⁺. **P < .01.