HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Supplemental Figure All Versions of this Article: 292/3/H1291    most recent 01017.2006v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Gurjarpadhye, A. Articles by Gourdie, R. G. Search for Related Content PubMed PubMed Citation Articles by Gurjarpadhye, A. Articles by Gourdie, R. G.

Cardiac neural crest ablation inhibits compaction and electrical function of conduction system bundles

¹Department of Cell Biology and Anatomy, Medical University of South Carolina; ²Clemson-Medical University of South Carolina Bioengineering Program, Department of Bioengineering, Clemson University, Charleston, South Carolina; ³Neonatal-Perinatal Research Institute-Neonatology, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina; ⁴Laboratory of Cardiovascular Morphogenesis, Institute of Animal Physiology and Genetics, Videnska; and ⁵Institute of Anatomy, First Faculty of Medicine, Charles University, Prague, Czech Republic

Submitted 17 September 2006 ; accepted in final form 5 December 2006

Retroviral and transgenic lineage-tracing studies have shown that neural crest cells associate with the developing bundles of the ventricular conduction system. Whereas this migration of cells does not provide progenitors for the myocardial cells of the conduction system, the question of whether neural crest affects the differentiation and/or function of cardiac specialized tissues continues to be of interest. Using optical mapping of voltage-sensitive dye, we determined that ventricles from chick embryos in which the cardiac neural crest had been laser ablated did not progress to apex-to-base activation by the expected stage [i.e., Hamburger and Hamilton (HH) 35] but instead maintained basal breakthroughs of epicardial activation consistent with immature function of the conduction system. In direct studies of activation, waves of depolarization originating from the His bundle were found to be uncommon in control hearts from HH34 and HH35 embryos. However, activations propagating from septal base, at or near the His bundle, occurred frequently in hearts from HH34 and HH35 neural crest-ablated embryos. Consistent with His bundle cells maintaining electrical connections with adjacent working myocytes, histological analyses of hearts from neural crest-ablated embryos revealed His bundles that had not differentiated a lamellar organization or undergone a process of compaction and separation from surrounding myocardium observed in controls. Furthermore, measurements on histological sections from optically mapped hearts indicated that, whereas His bundle diameter in control embryos thinned by almost one-half between HH30 and HH34, the His bundle in ablated embryos underwent no such compaction in diameter, maintaining a thickness at HH30, HH32, and HH34 similar to that observed in HH30 controls. We conclude that the cardiac neural crest is required in a novel function involving lamellar compaction and electrical isolation of the basally located His bundle from surrounding myocardium.

heart; His-Purkinje system

This article has been cited by other articles:

				Highlights From The Literature Physiology, April 1, 2007; 22(2): 70 - 72. [Full Text] [PDF]

				T. H. Rosenquist and R. H. Finnell Another key role for the cardiac neural crest in heart development Am J Physiol Heart Circ Physiol, March 1, 2007; 292(3): H1225 - H1226. [Full Text] [PDF]