Authors: Robert E Poelmann Daniël Molin Lambertus J Wisse Adriana C Gittenbergerde Groot
Publish Date: 2000/05/30
Volume: 301, Issue: 1, Pages: 43-52
Abstract
Cell degeneration as a phenomenon accompanying developmental processes was originally described over a century ago Apoptosis a term introduced approximately three decades ago has occupied investigators particularly with respect to cell and tissue kinetics emphasizing its role in the disposal of supernumerary malinstructed or damaged cells Although apoptosis is mostly related to developmental processes evidence has been gathered indicating that it may also perform other roles In this review which concentrates on cardiac development we examine focal apoptosis and subsequent signal cascades in combination with timed morphogenetic events Apoptosis mainly occurs in the nonmyocardial compartment of the embryonic heart a compartment that consists of cells derived from the endocardium the epicardium and the neural crest The lastmentioned population invades the outflow tract and the atrioventricular endocardial cushions The signalling cascade seems to involve the activation of latent transforming growth factor beta resulting in cardiomyocyte migration and subsequent myocardialization of the endocardial cushions Aberrant apoptosis accompanies cardiac anomalies Furthermore an apoptotic population is found surrounding the developing conduction system A possible role for differentiation is suggested
Keywords: