Heart conduction system: a neural crest derivative?
Using the anti-neurofilament monoclonal antibody iC8 we report here that muscle fibers of the conduction system of the adult and developing rabbit heart express a cytoskeletal protein antigenically and electrophoretically similar to the middle subunit of neurofilaments (NF-M). In the 11-day embryo a number of cardiac muscle cells also express a neural crest surface marker recognized by the monoclonal antibody HNK-1. Both markers are found in many cells of the 3rd and 4th branchial arches, which are populated by cells of neural crest origin. In the 11-day embryo cells of the 4th branchial arch are in close proximity to and intermingled with the atrial myocardium: cells co-expressing sarcomeric myosin heavy chain with iC8 and HNK-1 immunoreactivity are seen at these sites. The findings suggest that conduction tissue cells of the rabbit heart originate from a population of neural crest-derived cells migrating from the branchial arches into the developing heart.
Gorza
L
L
Institute of General Pathology, University of Padova, Italy.
Schiaffino
S
S
Vitadello
M
M
D000818:Animals; D006329:Heart Conduction System / Q000032:analysis* / Q000196:embryology; D007381:Intermediate Filament Proteins / Q000032:analysis*; D009432:Neural Crest / Q000032:analysis*; D011817:Rabbits
D007381:Intermediate Filament Proteins