Myocardial development in crocodylians

0565665 - FGÚ 2023 RIV US eng J - Journal Article
Kvasilová, A. - Gregorovičová, Martina - Olejníčková, Veronika - Kolesová, Hana - Sedmera, David
Myocardial development in crocodylians.
Developmental Dynamics. Roč. 251, č. 12 (2022), s. 2029-2047. ISSN 1058-8388. E-ISSN 1097-0177
R&D Projects: GA ČR(CZ) GA16-02972S; GA MŠMT(CZ) LTC17023; GA MŠMT(CZ) LM2015062; GA MŠMT(CZ) LX22NPO5104
Institutional support: RVO:67985823
Keywords : cardiac conduction system * crocodile embryo * heart * optical mapping * septation * vasculogenesis
OECD category: Developmental biology
Impact factor: 2.5, year: 2022
Method of publishing: Limited access
https://doi.org/10.1002/dvdy.527

Background:Recent reports confirmed the notion that there exists a rudimentary cardiac conduction system (CCS) in the crocodylian heart, and development of its ventricular part is linked to septation. We thus analyzed myocardial development with the emphasis on the CCS components and vascularization in two different crocodylian species.Results:Using optical mapping and HNK-1 immunostaining, pacemaker activity was localized to the right-sided sinus venosus. The atrioventricular conduction was restricted to dorsal part of the atrioventricular canal. Within the ventricle, the impulse was propagated from base-to-apex initially by the trabeculae, later by the ventricular septum, in which strands of HNK-1 positivity were temporarily observed. Completion of ventricular septation correlated with transition of ventricular epicardial activation pattern to mature apex-to-base direction from two periapical foci. Despite a gradual thickening of the ventricular wall, no morphological differentiation of the Purkinje network was observed. Thin-walled coronary vessels with endothelium positive for QH1 obtained a smooth muscle coat after septation. Intramyocardial vessels were abundant especially in the rapidly thickening left ventricular wall.Conclusions:Most of the CCS components present in the homeiotherm hearts can be identified in the developing crocodylian heart, with a notable exception of the Purkinje network distinct from the trabeculae carneae.
Permanent Link: https://hdl.handle.net/11104/0337181