2. CV System Flashcards
Vascular System Mission
maintain quality and volume of ECF via capillary bed
All cells must be ____ from capillary or will die
200 micro ms
Most variable tunic with SMCs and CT
Tunica Media (middle) = myocardium
Tunic made of CT and simple squamous cells. May host niche of adult cardiac SCs
Tunica Adventitia (Outer) = epicardium
Tunic with endothelium of ECs
Tunica Intima = endocardium
Endothelial cells are made of:
simple squamos cells with basal lamina
What stain do we use to identify cardiac muscle
PECAM~ CD31 cluster of differenation
During devo, the _____ cells grow over surface of heart in mono cell layer
epicardial cells
What three things to the epicardial cells give rise to?
Cardiac fibroblasts
coronary arteries (ECs and SMCs)
possibly cardiac monocytes
What are the three layers of the Large arteries?
- Adventitia: elastic
- Media: thickest w/ circuarl SMCs + 40-70 elastic lamellae
- Intima: ECs with tight jnx + pinocytic vesicles
Function of Large arteries
Elastic recoil and maintain BP during DIASTOLE
Clinical issue we can have with Large arteries
aneurysm
What is the thickest tunic in large veins
adventitia
Whats the most promiment layer in the Muscular arteries?
The Media: has 40 layers of SMC!!!! and less elastin
Whats a marker of the intima layer of the muscular artery?
interal elastic lamina …single
Function of the Muscular arteries
SMCs regulate BP
Where does atherosclerosis occur?
In muscluar artiers
Internal plaques from foam cells come from what?
Macrophages that ingest LDL
SMCs–> intima injest LDL
plaques calcify–> plats attache–> thrombus forms–> MI/Stroke
What comprises the Tunica media in small arteries and arterioles?
8 layers of SMC in small artery
2 layers of SMC in arterioles
Function of small arteries and arterioles
SMC regulates bloodflow to capillary bed
Lipid uptake by SMCs in the small arteries and arterioles will narrow the lumen and lead to
Hypertension
Diameter of the lumen of capillaries
~RBC or 7.5 micrometers
How many ECs makes up a capillary
I EC can make up a tube; simple squamous endothelium with basal lamina… NO adventitia, NO media
Continuous capillary
Has tight jnx~ allows only smaller then 10kDa
Pinocytic vesicles for proteins over 10kDA
Type I Capillary
Fenestrated capillary
have 100nm windows = permanent pino vesicles
Type II Caps
Sinusoidal capillary
Discontinuities and apx 30 micrometer diamerter
Type III Caps
Where are Type I Caps found and what do they transport
CNS, Heart, Lung, Skeletal Mscl
Oxygen exchange
Where are Type II caps found and what do they transport?
Endocrine glands, GI, Kidnesy
hormones/nutrients/ions
Where are Type III caps found and what do they transport
Bone marrow, liver, spleen
tranport whole cells
Main function of Endothelial Cells
- Exchange gases and nutrients
2. Secreate regulatory molecules
What vasoacitve factors are secreated by ECs?
Endothelin; vasoconstrictor
NO: vasorelaxant
What GFs are secreated by ECs
FGF, PDGF, VEGF~~ to activate angiogenesis
What is exchanged between the ECs?
Gases via cell membrane and nutrients via pino vesicles/fenestrations or dicontinuities
What is the first and last step of angiogenesis
- Activation of Endothelial cell receptors
7. Inhibition of angiogenic growth
Angiogenesis targets which type of cells
Endothelial Cells
What are Pro-Angiogenic therapies and what are they used for?
VEGF and FGF-induced BV formation for ischemia in heart and extremeties
What are Anti-angiogenic therapies and what are they used for?
angiostatin and endostatin.. to combat tumors
anti-VEGF mAB that inhibits BV formation and starves tumors
Bevacizumab
