Structural evidence for mechanisms to redistribute hepatic and ductus venosus blood flows in nonhuman primate fetuses

In nonhuman primate fetuses, the DV drains into a dilated ampullary area. An asymmetrical muscular lip forms a contractile element of the isthmic portion of the DV. The increased thickness of smooth muscle tissue in the DV isthmus and intrahepatic BPV in nonhuman primate fetuses support the concept of a general organization of a contractile apparatus that performs a sphincter-like function in the central venous hepatic system and plays a key role in blood flow redistribution.