Fig. 4

Protein expressions in CoA and the ductus arteriosus. Immunohistochemistry for prostaglandin E receptor EP4 (EP4; a), lysyl oxidase (b), and phosphodiesterase 3A (PDE3A; c) in the tissue of CoA with hypoplastic left heart syndrome (1-month-old patient). The expressions of EP4 and PDE3A were higher in the ductus arteriosus and ductal side of CoA, and lower in the aorta and aortic side of CoA. Lysyl oxidase was abundantly expressed in the aorta and aortic side of CoA, but not in the ductus arteriosus and ductal side of CoA. Immunohistochemical analysis was performed as previously described [44, 63]. Serial sections of Fig. 2 were used for immunohistochemistry. Scale bars 100 μm