REN and hydrops fetalis: As the most widely studied and commonly applied NP, BNP has the effects of diuresis, natriuresis, vasodilation, anti-hypertrophy and anti-fibrosis and it inhibits the renin-angiotensin-aldosterone and sympathetic nervous systems to maintain cardiorenal homeostasis and counteract the effects of HF (Semenov and Katrukha, 2016).