Neural crest cells in outflow tract septation of the embryonic chicken heart: Differentiation and apoptosis
Article first published online: 7 DEC 1998
Copyright © 1998 Wiley-Liss, Inc.
Volume 212, Issue 3, pages 373–384, July 1998
How to Cite
Poelmann, R.E., Mikawa, T. and Gittenberger-De Groot, A.C. (1998), Neural crest cells in outflow tract septation of the embryonic chicken heart: Differentiation and apoptosis. Dev. Dyn., 212: 373–384. doi: 10.1002/(SICI)1097-0177(199807)212:3<373::AID-AJA5>3.0.CO;2-E
- Issue published online: 7 DEC 1998
- Article first published online: 7 DEC 1998
- Manuscript Accepted: 20 FEB 1998
- Manuscript Received: 26 JUN 1997
- The Netherlands Organization for Scientific Research. Grant Number: NWO-R92-143
- The Netherlands Heart Foundation. Grant Number: 93.111
- NWO and Heart Foundation. Grant Number: 900-516-162
- neural crest;
- aortico-pulmonary septum;
- heart development;
- growth factor
The heart consists of cells deriving from the cardiogenic plate and also from extracardiac sources. One of the major extracardiac contributions is given by the neural crest. The differentiation pathway and fate of the neural crest cells in the outflow tract have been followed over a prolonged period during outflow tract septation. We studied the role of the neural crest in remodeling the outflow tract by long-term cell tracing, differentiation markers and apoptosis.
The pattern of neural crest cells migrating to the heart was investigated by heterospecific chicken quail chimeras and by retroviral infection of the reporter gene LacZ to the stemcells. The tagged neural crest cells move to areas that are morphogenetically active, such as the outflow tract, the semilunar valves, the wall of the arteries and the cardiac ganglia.
Two differentiated subpopulations are discerned on the basis of immunohistochemical characterization with antibodies against smooth muscle cells in the arterial vessel wall and against ganglionic cells that were scattered around the vessels of the arterial pole and the heart. A third subpopulation did not stain with these antibodies, but presented locally with the phenomenon of apoptosis as shown with the TUNEL approach.
In a developmental series of chicken embryos the populations were followed until stage 40. It was evident that the outflow tract septum in the early phase of development consisted mainly of mesenchymal neural crest cells. In a later phase neural crest cells were still detected at semilunar valve level, but nearly absent in the outflow tract septum below valve level. The septum at that time had become myocardialized. It is evident that neural crest cells are actually removed from this part of the heart by apoptosis. We are pursuing the hypothesis that an important function of apoptotic cells in heart development might be to activate the cardiomyocytes to muscularize the outflow tract septum through mobilizing or delivering growth factors at the time and place that septum formation is initiated. Dev. Dyn. 1998;212:373–384. © 1998 Wiley-Liss, Inc.