Pacing-induced ventricular remodeling in the chick embryonic heart

Details

Serval ID
serval:BIB_71EF6C0F196E
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Pacing-induced ventricular remodeling in the chick embryonic heart
Journal
Pediatric Research
Author(s)
Sedmera  D., Grobety  M., Reymond  C., Baehler  P., Kucera  P., Kappenberger  L.
ISSN
0031-3998 (Print)
Publication state
Published
Issued date
06/1999
Volume
45
Number
6
Pages
845-52
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Jun
Abstract
Chronic ectopic pacing in the adult heart induces myocardial hypotrophy close to the pacing site. We have recently described a similar localized decrease of compact myocardium thickness in the chick embryonic heart after 48 h of intermittent apical ventricular pacing. Here we analyze the cellular mechanisms underlying the response of the embryonic heart to pacing. Because the developing heart had been found to adjust its morphology according to functional demands by undergoing cellular hyperplasia or hypoplasia, we hypothesized that the stimulation should result in hypoplasia of the apical ventricular compartment. Morphologic analysis of hearts submitted to 18 h of effective pacing during 48 h showed a mild to moderate ventricular dilatation, a 28% decrease in the apical compact layer thickness with no changes in other ventricular locations, and atrial wall thickening. These modifications were caused by changes in the number of cell layers, whereas cell size was similar between paced and control hearts. Analysis of proliferative activity after 24 h of pacing showed a decrease of 32% in the rate of cell proliferation limited to the apical compact layer exposed to stimulation. No ultrastructural injury or increased cell death was found. These changes were accompanied by down-regulation of the myocardial growth factor fibroblast growth factor-2 but no differences were found in the expression of platelet-derived growth factor. Thus, chronic intermittent ventricular pacing induces myocardial remodeling in the chick embryonic heart, on the basis of locally regulated rates of cell proliferation.
Keywords
Animals Cardiac Pacing, Artificial/*adverse effects Cell Division Chick Embryo Fibroblast Growth Factor 2/metabolism Heart/*embryology Heart Defects, Congenital/embryology/etiology Heart Ventricles/embryology Immunohistochemistry Microscopy, Electron, Scanning Myocardium/cytology/metabolism Platelet-Derived Growth Factor/metabolism
Pubmed
Web of science
Open Access
Yes
Create date
15/02/2008 11:29
Last modification date
20/08/2019 14:30
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