title: Remodeling of aortic smooth muscle during avian embryonic development.
abstract: The dorsal aorta is the earliest formed intraembryonic blood vessel in vertebrates composed of an inner lining of endothelial cells (ECs) and a slightly later-forming outer wall consisting of vascular smooth muscle cells (SMCs) and pericytes. We previously identified the sclerotome as the only somitic compartment contributing to aortic SMCs in the trunk of the avian embryo. However, we demonstrated that the first SMCs in the aortic floor are not of somitic origin and must be derived from a different source. Here, we show that the primary SMCs are a transient population of aortic wall cells originating from the splanchnic mesoderm. A model is presented suggesting that wall formation of the early dorsal aorta in chick is a two-step process: The primary, transient SMCs in the aortic floor originate in the splanchnic mesoderm, whereas the secondary, definitive SMCs of the entire aortic wall originate in the sclerotome.
authors.affiliation: Institute of Anatomy and Cell Biology, Department of Molecular Embryology, University of Freiburg, Freiburg, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Wiegreffe
authors.forename: Bodo
authors.initials: B
authors.lastname: Christ
authors.forename: Ruijin
authors.initials: R
authors.lastname: Huang
authors.forename: Martin
authors.initials: M
authors.lastname: Scaal
mesh_terms: D000818:Animals; D001011:Aorta / Q000166:cytology* / Q000196:embryology*; D002454:Cell Differentiation; D048430:Cell Shape; D002642:Chick Embryo; D002645:Chickens; D008648:Mesoderm / Q000166:cytology / Q000196:embryology; D032389:Myocytes, Smooth Muscle / Q000166:cytology*