RYR2 and hydrops fetalis: Antagonism of angiotensin II was demonstrated to alleviate diminished SERCa2a activity in HF models (Okuda et al., 2004; Gassanov et al., 2006), while administration of AT1 blockers to STZ-diabetic rat cardiomyocytes reduced cellular oxidative stress as well as phosphorylation levels of RyR2, improving Ca2+ homeostasis (Privratsky et al., 2003; Yaras et al., 2007; Ozdemir et al., 2009).