Platelet and neutrophil NOX2 differentially regulate Ca²⁺ release and influx. Mouse platelets (A-B) and neutrophils (C-D) were pretreated with Ca²⁺ dye and then incubated with thrombin (0.025 U/mL [A]), fMLF (C), or thapsigargin (200 nM [B,D]) for 3-4 minutes and 2 mM CaCl₂ was then added. Intracellular Ca²⁺ release and SOCE were measured and quantified by the AUC (arbitrary units). Quantitative data represent the mean ± SD (n = 4-5). *P < .05 or **P < .01 vs WT after Student t test.