ORAI1 and hydrops fetalis: While there was no significant difference in STIM1 protein expression (0.19±0.02 vs 0.2±0.02, P=0.73; control n=3, hVF-HF n=8; Fig. 5A,B), the expression of ORAI1 was significantly greater in the hVF-HF group (0.09±0.008, n=8) than the control group (0.04±0.01, P=0.01, n=3; Fig. 5A,C).