Neural crest ablation does not alter pulmonary vein development in the chick embryo.

Abstract

Cranial neural crest, which extends from the mid-diencephalon to somite five, plays an integral role in development of pharyngeal arch derivatives and supplies mesenchyme to the aortic arch arteries. Neural crest cells in pharyngeal arches three, four, and six migrate to the heart and are involved in aorticopulmonary and conotruncal septation. Ablation of the "cardiac" neural crest cells in chick embryos results in a variety of outflow tract anomalies, including persistent truncus arteriosus. Although other studies have shown the importance of the neural crest in the development of the cardiac outflow tract, the role of neural crest in venous development has not been established. This investigation evaluates the effect of cardiac neural crest ablation on the morphological development of the pulmonary vein. The presence of the pulmonary vein was confirmed initially at early stage 15 using histological sections and computer reconstructions of serially sectioned, normal embryos. India ink injections demonstrated a complete, patent pulmonary circuit at stage 18. Cardiac neural crest was ablated at stages 8-10. Operated, sham-operated, and control embryos were sacrificed at incubation day 11, and acrylic plastic casts prepared of the intravascular compartment. In experimental embryos with persistent truncus arteriosus, there were no morphological differences in the pulmonary veins, compared with shams and controls. These data indicate that the lesions of the cardiac neural crest have little morphological impact on pulmonary vein development. It is concluded that alterations in the cardiac neural crest are not involved in venous anomalies such as cor triatriatum and total or partial anomalous pulmonary venous return.