Endocardial surface and atrial morphological changes during development and aging.
Title
Endocardial surface and atrial morphological changes during development and aging.
Creator
Gilloteaux J; Linz D
Publisher
The American journal of anatomy
Date
1989
1989-10
Description
Light, scanning, and transmission electron microscopic observations related to morphological changes of the right atrium as well as the atrial endocardium during development (15th embryonic day and 1 day old) and aging (560 days old) in the Syrian hamster were described and correlated. From the fetus to the adult, the atrial endocardium differentiates in parallel with, or in response to, the subjacent proliferating myocytes in the atrial wall and the trabeculae. Simultaneously, the atrium compartmentalizes grossly into a main chamber and an appendicular region. There is a progressive differentiation from a rudimentary, open chamber with primitive mural ridges in the fetal atria to a distinct, separate, atrial main chamber and appendage with a dense network of trabeculae in the adult. The fetal and neonatal endocardial, endothelial cells are convex with a central nuclear bulging and attenuated cytoplasmic extensions; the adult endocardium shows a squamous endothelium. Two cell surface specializations were observed in all age groups: microvilli and blebs or cytoplasmic protrusions. The general atrial morphology and surface endocardial changes were correlated with growth and the role of the endocardial endothelium as a barrier which controls metabolic exchanges, including the transport of atrial natriuretic factor, between the myocytes and the blood. This endothelial function appears to be essential in the fetal and neonatal age groups since no blood vessels are detected in these groups.
Subject
*Aging; Animals; Cricetinae; Electron; Embryonic and Fetal Development; Endocardium/embryology/growth & development/*ultrastructure; Endothelium/ultrastructure; Female; Heart Atria/embryology/growth & development/*ultrastructure; Male; Mesocricetus; Microscopy; Microvilli/ultrastructure; Pregnancy; Scanning
Identifier
Rights
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
Citation
Gilloteaux J; Linz D, “Endocardial surface and atrial morphological changes during development and aging.,” NEOMED Bibliography Database, accessed April 25, 2024, https://neomed.omeka.net/items/show/2938.