Ultrastructural aspects of atrium development: demonstration of endocardial discontinuities and immunolabeling of atrial natriuretic factor in the Syrian hamster.

Title

Ultrastructural aspects of atrium development: demonstration of endocardial discontinuities and immunolabeling of atrial natriuretic factor in the Syrian hamster.

Creator

Gilloteaux J

Publisher

Anatomy and embryology

Date

1989
1989

Description

The endocardium ultrastructure of 13 embryonic day old hamsters was examined, especially in relationship with the atrial myocytes. The endothelial morphology was described, including the junctional attachments and their relationships with subjacent atrial myocytes. Characteristic atrial myocytes organelles were identified: myofibrils, atrial granules, lipidic inclusions, and polysomes. Immunogold labeling demonstrated that atrial natriuretic factor (ANF)-containing granules were already present in the differentiating cardiomyocytes, even before the myofibrils were completely organized. At this stage of development, while the endothelium was a narrow barrier between the blood and the cardiomyocytes, it displayed fenestrations, but also epithelial discontinuities. In addition it also contains immunoreactive-ANF products. In light of the current knowledge about ANF processing it was proposed that the endocardium lining could be an obligated passageway for transport or activating proANF into ANF before its release into the blood stream. In addition the endocardial gaps could suggest that, until about 13 to 14 days of fetal development, heart atrial tissue could be more susceptible to the effects of pathogenetic compounds than in a later state of development.

Subject

Animals; Immunohistochemistry; Cricetinae; Microscopy; Atrial Natriuretic Factor/*analysis; Endocardium/analysis/*embryology/ultrastructure; Endothelium/analysis/embryology/ultrastructure; Heart Atria/analysis/embryology/ultrastructure; Electron

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).

Pages

227–236

Issue

3

Volume

179

Citation

Gilloteaux J, “Ultrastructural aspects of atrium development: demonstration of endocardial discontinuities and immunolabeling of atrial natriuretic factor in the Syrian hamster.,” NEOMED Bibliography Database, accessed March 28, 2024, https://neomed.omeka.net/items/show/5443.