Normal Development of the Muscular Region of the Interventricular Septum - I. The Significance of the Ventricular Trabeculations

• Published in: Anatomia, histologia, embryologia Vol. 37; no. 5; pp. 344 - 351
• Main Authors: Contreras-R.amos, A, Sánchez-G.ómez, C, García-R.omero, H.L, Cimarosti, L.O
• Format: Journal Article
• Language: English
• Published: Oxford, UK Oxford, UK : Blackwell Publishing Ltd 01.10.2008; Blackwell Publishing Ltd
• Subjects: Animals; Chick Embryo - anatomy & histology; Gestational Age; Heart - embryology; Heart Septum - embryology; Heart Septum - ultrastructure; Heart Ventricles - embryology; Heart Ventricles - ultrastructure; Morphogenesis
• ISSN: 0340-2096; 1439-0264
• DOI: 10.1111/j.1439-0264.2008.00852.x

The structures that participate in normal ventricular septation, and to what extent they do so, are questions not yet clarified. Even less is known about how much each of the embryonic structures contributes to the topography of the mature interventricular septum (IVS). The aim of the present paper is to investigate the significance of ventricular trabeculations in the normal development of the muscular region (the middle and apical thirds) of the IVS and to determine the direction in which it grows during cardiac septation. Anatomical studies and in vivo labelling were carried out in chicken embryo hearts at stage 18HH, tracing the labels up to stage 36HH. We analysed the results by measuring the distance between the labelled structures at the beginning and end of the experiments. We demonstrate that the muscular region of the septum originates by the fusion of the ventricular trabeculations with evidence that during cardiac development, the IVS as well as the ventricular cavities grow in opposite direction to the atria.