Vascular Smooth Muscle Cells (AAA)

Vascular smooth muscle cells arising from neural crest cells form multiple concentric layers around the endothelial layer of the aortic arch artery derivatives and the distal continuations of the great arteries. The most proximal walls of the aorta and pulmonary trunks are not covered by neural crest-derived smooth muscle cells. This region is populated by cells from the secondary heart field (SHF). Hence, the smooth muscle contributed by SHF cells form the tunica media, at the base of the aorta, and the pulmonary trunk, at the aortic and pulmonary sinuses.