SRC and hydrops fetalis: Western blot results showed that for all five complexes, protein levels decreased in HF and HF + HIIT + shMetrnl, compared with Con, which was reversed back towards Con levels or even higher in HF + HIIT + Src-shRNA and HF + Metrnl, indicating that increased Metrnl is associated with increased complexes I–V (Fig. 7E, F).