Document Detail


Anatomy and histology of the cardiac conal valves of the adult dogfish (Scyliorhinus canicula).
MedLine Citation:
PMID:  7604964     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
BACKGROUND: Knowledge of the structural arrangement of the cardiac conal valves in Elasmobranchs is scarce. The present study was designed to assess the anatomical and histological features of the conal valves of the dogfish as a starting point for further investigation of the mechanical properties of these valves. METHODS: The sample examined consisted of 31 adult dogfishes. The study was carried out using scanning electron microscopy and histological techniques for light microscopy. RESULTS: In the dogfish, the conus arteriosus contains two transverse rows of valves. The anterior row lies at the level of the conus-ventral aorta junction and is composed of three valves of similar size. The posterior row is near the conus-ventricular junction and consists of four valves, one of them very reduced in size. Each valve shows two components, namely, the leaflet and its supporting structure, the sinus. In the anterior valves, the length of the leaflets between their lateral attachments to the sinus wall is remarkably longer than the straight-line distance between the points of attachment. This allows each leaflet to close against the other two leaflets of the same row, even when the conus is relaxed. The leaflets of the posterior valves are anchored to the conus wall by means of tendinous cords and cannot practically bridge the lumen of the relaxed conus. Each leaflet has a stout central body in which the connective tissue is stratified in three layers: outer fibrosa, spongiosa, and inner fibrosa. The lateral parts of the leaflet mainly consist of a single fibrous layer that bifurcates into the outer and inner fibrosa layers of the central body. The sinus walls of the posterior valves are entirely made up of conal tissue, whereas those of the anterior valves incorporate an aortic component. CONCLUSIONS: The present findings suggest that the inner fibrosa and the fibrous lateral portions of the leaflets mainly bear the stress of pressure generated by blood backflow. The stretching of the leaflets in the radial direction may basically depend on the spongiosa, whereas the outer fibrosa determines the radial stiffness of the leaflets.
Authors:
V Sans-Coma; A Gallego; R Muñoz-Chápuli; A V De Andrés; A C Durán; B Fernández
Related Documents :
2809564 - Reconstruction of right ventricular outflow tract by autologous pericardial tri-semilun...
24480704 - The influence of vascular anatomy on carotid artery stenting: a parametric study for da...
25042904 - Gestational age-specific scoring systems for the prediction of coarctation of the aorta.
22965244 - Local hemodynamics at the rupture point of cerebral aneurysms determined by computation...
10473294 - The porcine bronchial artery. anastomoses with oesophageal, coronary and intercostal ar...
24299944 - Increased oxidative stress and xanthine oxidase activity in human ruptured cerebral ane...
Publication Detail:
Type:  In Vitro; Journal Article    
Journal Detail:
Title:  The Anatomical record     Volume:  241     ISSN:  0003-276X     ISO Abbreviation:  Anat. Rec.     Publication Date:  1995 Apr 
Date Detail:
Created Date:  1995-08-10     Completed Date:  1995-08-10     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0370540     Medline TA:  Anat Rec     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  496-504     Citation Subset:  IM    
Affiliation:
Department of Animal Biology, Faculty of Science, University of Málaga, Spain.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Dogfish / anatomy & histology*
Female
Heart Valves / anatomy & histology*
Male
Microscopy, Electron, Scanning

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Ultrastructure and protein transport of M cells in the rabbit cecal patch.
Next Document:  Skeletal alterations in hypophysectomized rats: I. A histomorphometric study on tibial cancellous bo...