Tags: Anatomical Structure, Embryology.
The aortic bulb or aortic sac is a dilated structure in mammalian embryos lined by endothelial cells located just above (distal to) the truncus arteriosus. It is the primordial vascular channel from which the aortic arches arise (and eventually the dorsal aortae) and is homologous to the ventral aorta of gill-bearing vertebrates.Genes dHAND and eHAND are expressed during the development of the aortic bulb and the arteries which arise from it.
