ADRB2 and hydrops fetalis: Western blot assay revealed that the relative expression of Hhip, Adrb2, Rac2, and protein kinase A (PKA) was significantly higher in the HF BMS than in the HF LT group (P < 0.05, P < 0.001, P < 0.05, P < 0.05, respectively; Fig. 8B–E).