Talk:Cardiovascular System - Developmental Shunts: Difference between revisions
(Created page with "{{Talk Page}} ==1983== ===Hepatic and ductus venosus blood flows during fetal life=== Hepatology. 1983 Mar-Apr;3(2):254-8. Rudolph AM. Abstract The course of the venous circ...") |
No edit summary |
||
| Line 1: | Line 1: | ||
{{Talk Page}} | {{Talk Page}} | ||
==2011== | |||
===Prenatal cardiovascular shunts in amniotic vertebrates=== | |||
Respir Physiol Neurobiol. 2011 Apr 13. [Epub ahead of print] | |||
Dzialowski EM, Sirsat T, van der Sterren S, Villamor E. | |||
Source | |||
Department of Biological Sciences, University of North Texas, Denton, TX 76203, USA. | |||
Abstract | |||
During amniotic vertebrate development, the embryo and fetus employ a number of cardiovascular shunts. These shunts provide a right-to-left shunt of blood and are essential components of embryonic life ensuring proper blood circulation to developing organs and fetal gas exchanger, as well as bypassing the pulmonary circuit and the unventilated, fluid filled lungs. In this review we examine and compare the embryonic shunts available for fetal mammals and embryonic reptiles, including lizards, crocodilians, and birds. These groups have either a single ductus arteriosus (mammals) or paired ductus arteriosi that provide a right-to-left shunt of right ventricular output away from the unventilated lungs. The mammalian foramen ovale and the avian atrial foramina function as a right-to-left shunt of blood between the atria. The presence of atrial shunts in non-avian reptiles is unknown. Mammals have a venous shunt, the ductus venosus that diverts umbilical venous return away from the liver and towards the inferior vena cava and foramen ovale. Reptiles do not have a ductus venosus during the latter two thirds of development. While the fetal shunts are well characterized in numerous mammalian species, much less is known about the developmental physiology of the reptilian embryonic shunts. In the last years, the reactivity and the process of closure of the ductus arteriosus have been characterized in the chicken and the emu. In contrast, much less is known about embryonic shunts in the non-avian reptiles. It is possible that the single ventricle found in lizards, snakes, and turtles and the origin of the left aorta in the crocodilians play a significant role in the right-to-left embryonic shunt in these species. | |||
Copyright © 2011. Published by Elsevier B.V. | |||
PMID: 21513818 | |||
==1983== | ==1983== | ||
Revision as of 08:28, 6 May 2011
| About Discussion Pages |
|---|
Glossary Links
Cite this page: Hill, M.A. (2024, June 27) Embryology Cardiovascular System - Developmental Shunts. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Cardiovascular_System_-_Developmental_Shunts |
2011
Prenatal cardiovascular shunts in amniotic vertebrates
Respir Physiol Neurobiol. 2011 Apr 13. [Epub ahead of print]
Dzialowski EM, Sirsat T, van der Sterren S, Villamor E. Source Department of Biological Sciences, University of North Texas, Denton, TX 76203, USA.
Abstract
During amniotic vertebrate development, the embryo and fetus employ a number of cardiovascular shunts. These shunts provide a right-to-left shunt of blood and are essential components of embryonic life ensuring proper blood circulation to developing organs and fetal gas exchanger, as well as bypassing the pulmonary circuit and the unventilated, fluid filled lungs. In this review we examine and compare the embryonic shunts available for fetal mammals and embryonic reptiles, including lizards, crocodilians, and birds. These groups have either a single ductus arteriosus (mammals) or paired ductus arteriosi that provide a right-to-left shunt of right ventricular output away from the unventilated lungs. The mammalian foramen ovale and the avian atrial foramina function as a right-to-left shunt of blood between the atria. The presence of atrial shunts in non-avian reptiles is unknown. Mammals have a venous shunt, the ductus venosus that diverts umbilical venous return away from the liver and towards the inferior vena cava and foramen ovale. Reptiles do not have a ductus venosus during the latter two thirds of development. While the fetal shunts are well characterized in numerous mammalian species, much less is known about the developmental physiology of the reptilian embryonic shunts. In the last years, the reactivity and the process of closure of the ductus arteriosus have been characterized in the chicken and the emu. In contrast, much less is known about embryonic shunts in the non-avian reptiles. It is possible that the single ventricle found in lizards, snakes, and turtles and the origin of the left aorta in the crocodilians play a significant role in the right-to-left embryonic shunt in these species.
Copyright © 2011. Published by Elsevier B.V.
PMID: 21513818
1983
Hepatic and ductus venosus blood flows during fetal life
Hepatology. 1983 Mar-Apr;3(2):254-8.
Rudolph AM.
Abstract
The course of the venous circulation in the fetal liver has been studied in fetal lambs by means of the radionuclide-labeled microsphere technique. About 50% of umbilical venous blood passes through the ductus venosus, while the remainder is distributed to both lobes of the liver. Portal venous blood is largely distributed to the right lobe of the liver, with a small proportion passing through the ductus venosus and none to the left lobe. Because of these flow patterns, oxygen saturation is lower in the right than in the left hepatic vein. Left hepatic venous blood joins the ductus venosus stream and these preferentially pass through the foramen ovale, whereas right hepatic venous blood joins the distal inferior vena caval stream and preferentially passes through the tricuspid valve. These patterns favor distribution of well-oxygenated blood to the fetal heart and brain. Hypoxia and reduced umbilical venous return are associated with reduced flow through the hepatic microcirculation with proportionately greater ductus venosus flow. In the fetus, the liver has a major role in influencing venous return to the heart and in regulating distribution of oxygen and energy substrate supply to different fetal organs.
PMID: 6832717
