Epicardial development in the rat: a new perspective.
Development of the epicardium is critical to proper heart formation. It provides all of the precursor cells that form the coronary system and supplies signals that stimulate cardiac myocyte proliferation. The epicardium forms from mesothelial cells associated with the septum transversum and is referred to as the proepicardium (PE). Two different methods by which these PE cells colonize the developing heart have been described. In avians, PE cells form a bridge to the heart over which PE cells migrate onto the heart. In fish and mammals, PE cells form vesicles of cells that detach from the mesothelium, float through the pericardial cavity, and attach to the heart. A previous study of rat PE development investigated this process at the histological level. Protein markers have been developed since this study. Thus, we investigated this important developmental process coupled with these new markers using other visualization techniques such as scanning electron microscopy (SEM) and confocal microscopy. Finally, a novel, three-dimensional (3-D) culture system was used to confirm the identity of the PE cells. In this study, we found convincing evidence that the rat PE cells directly attach to the heart in a manner similar to that observed in avians.
Nesbitt
Tresa
T
Department of Cell & Developmental Biology and Anatomy, University of South Carolina, School of Medicine, Columbia, SC 29209, USA.
Lemley
Aubrey
A
Davis
Jeff
J
Yost
Michael J
MJ
Goodwin
Richard L
RL
Potts
Jay D
JD
D000818:Animals; D002448:Cell Adhesion; D002465:Cell Movement; D005260:Female; D005865:Gestational Age; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D007633:Keratins / Q000378:metabolism; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D032383:Myocytes, Cardiac / Q000166:cytology / Q000378:metabolism; D009218:Myosins / Q000378:metabolism; D010496:Pericardium / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D011247:Pregnancy; D011784:Quail / Q000196:embryology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013045:Species Specificity
D007633:Keratins; D009218:Myosins