Endothelium Flashcards
What blood pressure do arteries flow at
80-120mm Hg
What pressure do veins flows at?
30 mm Hg
What pressure do capillaries flow at?
8-10 mm Hg
Structure of capillary
Thing endothelial barrier between ECM and blood with fenestrations
Examples of endothelial input-output activity
Cell adhesion, response to growth factors, interaction with migrating cells, cell life balance
Endothelium physiological features
Vasculogenesis
Angiogenesis
Vascular homeostasis
Blood clotthing
Endothelial adhesive functions
- Provision of an intercellular barrier
- Regulates molecule and particle movement/trafficking
- Regulation of cell movement/trafficking
- Cell barrier regulates angiogenesis & vasculogenesis
What cells promote angiogenesis
Endothelial cells
How does angiogenesis link to cancer
Solid tumour growth tepends on angiogenesis, also metastasis of cancer
How does hypoxia stimulate angiogenesis
- Promotes solid tumour growth and spread
- Hypoxia promotes synthesis of pro-angiogenic factors
- Hypoxia promotes VEGF-A gene expression
- Increased VEGF-A secretion stimulates angiogenesis
Angiogenesisi and VEGF-A
Dependent on HIF-1 activity
* Synthesis of proteins such as VEGF-A
* VEGF-A is secreted and binds to cognate receptors on the endothelium
* Blocking signallingin cancer e.g. Avastin
HIF activity in health and disease
- Oxygen regulates multiple vascular responses via HIFs
- Oxygen regulates multiple disease states via HIFs
- HIFs are potential drug targets in disease states
What is the endothelial glycocalyx?
Very sensitive endothelial layer to many different stimuli
What does VEGFR control
Growth and survival
What do blood vessels sprouts express
DII4
