L16-17: Vasculature Development Flashcards
(45 cards)
Are signalling pathways in veins and arteries different?
No.
What does ephrin B2 signalling do?
- promote directional cell migration and invasion
- suppress cell apoptosis
What is angiogenesis and vasculogenesis?
Vasculogenesis is formation of new blood vessels
Angiogenesis is branching from existing vessels to create new ones
Cell transitions in becoming blood vessels
mesoderm > hemangioblasts > angioblasts > endothelial cells
Where is extraemryonic vasculogenesis taking place?
in the yolk sac
Where is intraembryogenic vasculogenesis taking place?
dorsal aorta and vessels between organs
What are the steps in vasculogenesis?
- condensation
- Differentiation
- epithelialization
What inhibits the proliferation of endothelial cells?
contact with the capillary basement membrane
What are some markers of quiescent endothelial cells?
PECAM, L-selectin
What are some markers of angiogenic endothelial cells?
TFG-β receptor
What are the three types of endothelial cells? Where are they found
continuous. muscle, brain, heart
fenestrated, discontinuous. endo/exocrine organs. for easier transport
what the big difference between discontinous and continous/fenestrated endo cells
No basal membrane on discontinuous
What are some support cells that wrap around the endothelial cells?
pericytes and other mural cells
What connects mural cells to endo cells?
angiopoetins on mural cells and Tie2 receptors on endo cells
What type of cell give rise to endo and mural cells?
vascular progenitor
Which VEGFR can exist in free soluble but inactive form?
VEGFR1
Which receptors can bind VEGFA?
VEGFR 1 and 2
Which VEGFR is not necessary in angiogenesis?
VEGFR 3
What would happen without mural cells?
severe edema. makes sense because there would vasodialation without control?
What is interesting about VEGFR1 role in vasculogenesis?
Even without the kinase domain, it had no negative effect on vasculogenesis. But total removal results in lower vasculogenesis.
What is the primary role of VEGFR1?
Recruit macrophages to release
What is essential for vasculogensis and what is not?
VEGFR2 and VEGFA is.
VEGFR1 is not
What are three functions of VEGFR2?
proliferation, survival and motility
Describe how boyden chamber assay works
Plate cells. Put chemoattractants and see the migration of the cells above or below the plate