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PubMed · 12956324

Developmental transitions in cardiac conduction.

Michiko Watanabe·Emil Thomas Chuck·Florence Rothenberg·David S Rosenbaum
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Abstract

The proper sequence of electrical activation of the mature four-chambered heart requires specialized conduction pathways including the His-Purkinje system and a nearly complete separation of the atrial and ventricular myocardium. We tracked the emergence of the structure of the mature His-Purkinje system in the developing chicken embryo with anti-polysialylated neural cell adhesion molecule (PSA-NCAM) and the HNK1 antibody against a sulfated carbohydrate epitope. The function of the His-Purkinje system was assayed using extracellular electrodes and high-resolution voltage-sensitive two-dimensional optical mapping. The appearance of the mature form of the His-Purkinje system delineated by the markers coincided with the onset of the mature electrophysiological pattern of ventricular activation. These data suggest that, at the completion of ventricular septation, the His-Purkinje system undergoes critical structural and functional transitions that impact on the global pattern of conduction and contraction of the developing four-chambered heart.

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Action PotentialsAnimalsApoptosisChick EmbryoElectrocardiographyHeartHeart Conduction SystemMyocardiumJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.Review

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Michiko Watanabe, Emil Thomas Chuck, Florence Rothenberg, David S Rosenbaum. 2003. Developmental transitions in cardiac conduction.. https://pubmed.ncbi.nlm.nih.gov/12956324/

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