Cardiovascular System - Blood Vessel Development: Difference between revisions
(Created page with '<div style="background:#F5FFFA; border: 1px solid #CEF2E0; padding: 1em; margin: auto; width: 95%; float:left;"><div style="margin:0;background-color:#cef2e0;font-family:sans-ser…') |
|||
| Line 3: | Line 3: | ||
== Introduction == | == Introduction == | ||
Blood develops initially within the core of "blood islands" in the mesoderm. | Blood develops initially within the core of "blood islands" in the mesoderm. During development, there follows a series of "relocations" of the stem cells to different organs within the embryo. In the adult, these stem cells are located in the bone marrow. At the time when blood first forms, there are no bones! | ||
During development, there follows a series of "relocations" of the stem cells to different organs within the embryo. | |||
In the adult, these stem cells are located in the bone marrow. At the time when blood first forms, there are no bones! | |||
Angioblasts initially form small cell clusters (blood islands) within the embryonic and extraembryonic mesoderm. These blood islands extend and fuse together making a primordial vascular network. Within these islands the peripheral cells form endothelial cells while the core cells form blood cells (haemocytoblasts). | Angioblasts initially form small cell clusters (blood islands) within the embryonic and extraembryonic mesoderm. These blood islands extend and fuse together making a primordial vascular network. Within these islands the peripheral cells form endothelial cells while the core cells form blood cells (haemocytoblasts). | ||
<center>Fetal blood vessel</center> | <center>Fetal blood vessel</center> | ||
| Line 18: | Line 11: | ||
Recent work has shown that the formation of the initial endothelial tube is by a process of coalescence of cellular vacuoles within the developing endothelial cells, which fuse together without cytoplasmic mixing to form the blood vessel lumen. | Recent work has shown that the formation of the initial endothelial tube is by a process of coalescence of cellular vacuoles within the developing endothelial cells, which fuse together without cytoplasmic mixing to form the blood vessel lumen. | ||
Blood Vessel Formation | |||
(Image: Developmental biology: The hole picture Keith Mostov and Fernando Martin-Belmonte Nature 442, 363-364 27 July 2006) | |||
:{{Template:Heart Links}} | :{{Template:Heart Links}} | ||
== Some Recent Findings == | == Some Recent Findings == | ||
Revision as of 17:27, 31 July 2010
Introduction
Blood develops initially within the core of "blood islands" in the mesoderm. During development, there follows a series of "relocations" of the stem cells to different organs within the embryo. In the adult, these stem cells are located in the bone marrow. At the time when blood first forms, there are no bones!
Angioblasts initially form small cell clusters (blood islands) within the embryonic and extraembryonic mesoderm. These blood islands extend and fuse together making a primordial vascular network. Within these islands the peripheral cells form endothelial cells while the core cells form blood cells (haemocytoblasts).
Recent work has shown that the formation of the initial endothelial tube is by a process of coalescence of cellular vacuoles within the developing endothelial cells, which fuse together without cytoplasmic mixing to form the blood vessel lumen.
Blood Vessel Formation
(Image: Developmental biology: The hole picture Keith Mostov and Fernando Martin-Belmonte Nature 442, 363-364 27 July 2006)
Some Recent Findings
[1]Developmental origin of smooth muscle cells in the descending aorta in mice. Development. 2008 May;135(10):1823-32. (More? [../Notes/skmus6.htm Musculoskeletal Development - Mesoderm/Somite])
"Aortic smooth muscle cells (SMCs) have been proposed to derive from lateral plate mesoderm. ....(these results) suggested that all SMCs in the adult descending aorta derive from the somites, whereas no contribution was recorded from lateral plate mesoderm."
[2]Endothelial expression of the Notch ligand Jagged1 is required for vascular smooth muscle development. Proc Natl Acad Sci U S A. 2008 Feb 1;
"The Notch ligand Jagged1 (Jag1) is essential for vascular remodeling. ...Jag1 null phenotype. These embryos show striking deficits in vascular smooth muscle, whereas endothelial Notch activation and arterial-venous differentiation appear normal."
[3]"In sprouting angiogenesis, specialized endothelial tip cells lead the outgrowth of blood-vessel sprouts towards gradients of vascular endothelial growth factor (VEGF)-A. ...suggest that Dll4-Notch1 signalling between the endothelial cells within the angiogenic sprout serves to restrict tip-cell formation in response to VEGF, thereby establishing the adequate ratio between tip and stalk cells required for correct sprouting and branching patterns."
[4] "More than 25 years ago, in some of the first endothelial cell culture experiments in vitro, Folkman and Haudenschild described "longitudinal vacuoles" that "appeared to be extruded and connected from one cell to the next" "...Here we use high-resolution time-lapse two-photon imaging of transgenic zebrafish to examine how endothelial tubes assemble in vivo, comparing our results with time-lapse imaging of human endothelial-cell tube formation in three-dimensional collagen matrices in vitro. Our results provide strong support for a model in which the formation and intracellular and intercellular fusion of endothelial vacuoles drives vascular lumen formation."
Endothelial Progenitors
Recent work has shown that the formation of the initial endothelial tube is by a process of coalescence of cellular vacuoles within the developing endothelial cells, which fuse together without cytoplasmic mixing to form the blood vessel lumen.
Endothelial Tube Formation
Stimulators of Angiogenisis (Blood Vessel Growth)
- Peptide growth factors
- Vascular endothelial growth factor-Aa,b, -Bb, -Cb, -D
- [-E], -F (VEGF-Aa,b, -Bb, -Cb, -Db, -E, -F)
- Placenta growth factor (PlGF)
- Angiopoietin-1 (Ang-1)
- Angiopoietin-2 (Ang-2) [modulator in the presence of angiogenic activity]
- Acidic fibroblast growth factor (FGF-1)
- Basic fibroblast growth factor (FGF-2)
- Platelet-derived growth factor (PDGF)
- Transforming growth factor-a (TGF-a)
- Transforming growth factor-b (TGF-b)
- Hepatocyte growth factor (HGF)
- Insulin-like growth factor-I (IGF-I)
- Multifunctional cytokines/immune mediators
- Tumour necrosis factor-a (low-dose)
- Monocyte chemoattractant protein-1 (MCP-1)
- CXC-chemokines
- Interleukin-8 (IL-8)
- Enzymes
- Platelet-derived endothelial cell growth factor
- (PD-ECGF; thymidine phosphorylase)
- Angiogenin (ribonuclease A homologue)
- Hormones
- Oestrogens
- Prostaglandin-E1, -E2
- Follistatin
- Proliferin
- Oligosaccharides
- Hyaluronan oligosaccharides
- Gangliosides
(data from table 1 Vascular morphogenesis in the ovary, Augustin H.G Bailliere's Clinical Obstetrics and Gynaecology 14:867-882, 2000)
Inhibitors of Angiogenisis (Blood Vessel Growth)
- Peptide growth factors and proteolytic peptides
- Angiopoietin-2 (Ang-2) [in the absence of angiogenic activity]
- Angiostatin
- Endostatin
- 16 kDa prolactin fragment
- Laminin peptides
- Fibronectin peptides
- Inhibitors of enzymatic activity
- Tissue metalloproteinase inhibitors
- (TIMP-1, -2, -3, -4)
- Plasminogen activator inhibitors
- (PAI-1, -2)
- Multifunctional cytokines/immune mediators
- Tumour necrosis factor-a (high-dose)
- Interferons
- Interleukin-12
- CXC-chemokines
- Platelet factor-4 (PF-4)
- Interferon-gamma-inducible protein-10 (IP-10)
- Gro-beta
- Extracellular matrix molecules
- Thrombospondin
- Hormones/metabolites
- 2-Methoxyestradiol (2-ME)
- Proliferin-related protein
- Oligosaccharides
- Hyaluronan, high-molecular-weight species
(data from table 1 Vascular morphogenesis in the ovary, Augustin H.G Bailliere's Clinical Obstetrics and Gynaecology 14:867-882, 2000)
Vascular Endothelial Growth Factor
Growing blood vessels follow a gradient generated by tagret tissues/regions of Vascular Endothelial Growth Factor (VEGF) to establish a vascular bed. Recent findings suggest that Notch signaling acts as an inhibitor for this system, preventing sprouting of blood vessels.
Notch is a transmembrane receptor protein involved in regulating cell differentiation in many developing systems.
Links: OMIM - VEGFA | OMIM - Notch
Cardiac Blood Vessels
Earliest vessels in the heart wall develop subepicardially (beneath the outside surface of the heart) near the apex at Carnegie stage 15, which then extends centripetally and at stage 17 coronary arterial stems communicate with the aortic lumen.
(Text modified from: [12])
References
Search Pubmed Now
Click on the listed keywords below (used to search the external database) the most current references on Medline will be displayed.
[TITL+development[WORD]+review[WORD]&doptcmdl=DocSum blood[TITL]+development[WORD]+review[WORD]]
Blood Vessel Development Terms
- angioblasts stem cells in blood islands generating endothelial cells
- angiogenesis the formation of blood vessels also called vasculogenesis in the embryo
- blood islands earliest sites of blood vessel and blood cell formation, seen mainly on yolk sac chorion
- vascular endothelial growth factor (VEGF) protein growth factor family that stimulates blood vessel growth, a similar factor can be found in the placenta (PIGF).
Glossary Links
- Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers | Symbols | Term Link
Cite this page: Hill, M.A. (2024, April 18) Embryology Cardiovascular System - Blood Vessel Development. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Cardiovascular_System_-_Blood_Vessel_Development
- © Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G
- ↑ <pubmed>18417617</pubmed>
- ↑ <pubmed>18245384</pubmed>
- ↑ <pubmed>17259973</pubmed>
- ↑ <pubmed>16799567</pubmed>
- ↑ <pubmed>16794034</pubmed>
- ↑ <pubmed>11827993</pubmed>
- ↑ <pubmed>16799567</pubmed>
- ↑ <pubmed>16453301</pubmed>
- ↑ <pubmed>12610662</pubmed>
- ↑ <pubmed>10487846</pubmed>
- ↑ <pubmed>6160403</pubmed>
- ↑ <pubmed>8915616</pubmed>
- ↑ <pubmed>10948449</pubmed>
- ↑ <pubmed>12406884</pubmed>
