Vascular bio II

Question 1

What are the three types of capillaries?

Answer 1

Continuous
Fenestrated
Sinusoidal

Question 2

What type of junction exists between cells of a continuous capillary?

Answer 2

Tight junctions (zonulae occludens)

Question 3

If a ZO is incomplete, what is it then called?

Answer 3

Fascia occludens

Question 4

What is the fold that covers up the tight junctions between the cells of continuous capillaries?

Answer 4

Marginal fold

Question 5

What is present in large amounts in the cytoplasm of continuous capillaries?

Answer 5

Pinocytotic vesicles

Question 6

How are transendothelial channels formed in continuous capillaries?

Answer 6

Fusion of many pinocytotic vesicles

Question 7

Where are continuous capillaries found?

Answer 7

Brain
Lung
Muscle
CT
Exocrine glands

anywhere where you want specific transport

Question 8

What are the two types of fenestrated capillaries?

Answer 8

With and without a diaphragm

Question 9

True or false: the basal lamina is discontinuous in fenestrated capillaries?

Answer 9

False

Question 10

Where are fenestrated capillaries found?

Answer 10

Kidney
Endocrine glands
Intestines
Glomerulus (diaphragms absent here)

Anywhere where movement of ions is preferred

Question 11

Do most fenestrated capillaries have diaphragms?

Answer 11

Yes, most do

Question 12

What is different about the basal lamina in sinusoidal capillaries?

Answer 12

either very discontinuous or absent

Question 13

Where are sinusoidal capillaries found?

Answer 13

Red bone marrow
Liver
Spleen
Adrenal cortex

Wherever rapid movement is needed

Question 14

What are the two types of venules?

Answer 14

Pericytic and muscular venules

Question 15

Where do leukocytes attach in veinules?

Answer 15

At the marginal fold

Question 16

Why is the tunica media thin in veinules?

Answer 16

Low pressure

Question 17

What is the thickest layer of veinules?

Answer 17

the tunica adventitia

Question 18

What are present in veins that are entirely absent in arteries?

Answer 18

valves

Question 19

What are present in arteries that are entirely absent in veins?

Answer 19

Lamellae

Question 20

What is characteristic of medium veins, as compared to smaller veins?

Answer 20

Small amount of smooth muscle

Question 21

What is the defining characteristic of large veins?

Answer 21

Bundles of longitudinally smooth muscles in he tunica adventitia (NOT the tunica media)

Question 22

What is vasculogenesis?

Answer 22

de novo vessel formation

Question 23

What is angiogenesis?

Answer 23

Growth of vessels from existing EC derived channels

Question 24

What is arteriogenesis?

Answer 24

Formation of arteries, arterioles, and collateral vassel remodeling

Question 25

What is neovascularization?

Answer 25

overarching term to include the three genesis terms

Question 26

What is remodeling (in terms of vessels)?

Answer 26

vascular response to alterations in the environment

Question 27

Where are endothelial cells precursors found?

Answer 27

In red bone marrow

Question 28

What are endothelial cepp precursors?

Answer 28

angioblast-like cells that reside in the red bone marrow of adults and non-bone marrow niches

Question 29

What are the three functions of EPCs?

Answer 29

1. Replaces lost endothelial cells 2. Re-endothelization of vascular implants (stents) 3. Neovascularization of ischemic organs, wounds, and tumors

Question 30

What is the first step of angiogenesis?

Answer 30

Vasodilation due to NO and increased vascular permeability induced by VEGF of pre-existing (parent) vessel

Question 31

What is the second step of angiogenesis?

Answer 31

Proteolytic degradation of the basal lamina of the parent vessel by metalloproteinases. Endothelial cells must shed their cell-to-cell contacts (intercellular junctions). This loss of cell-to-cell contact is mediated by plasminogen activator.

Question 32

What is the third step of angiogenesis?

Answer 32

Migration and proliferation of endothelial cells which have disrupted their cell-to-cell contacts. The migration and proliferation is induced by proangiogenic factors (e.g., VEGF and angiopoietin 2). Fibroblast growth factor-2 can also mediate endothelial cell migration and proliferation.

Question 33

What is the fouth step of angiogenesis?

Answer 33

Endothelial cells mature into an endothelial capillary tube.

Question 34

What is the fifth step of angiogenesis?

Answer 34

Elaboration of basal lamina and recruitment of periendothelial cells. Elaboration of basal lamina elements is mediated by TGF-β (transforming growth factor). Recruitment of periendothelial cells is mediated by the interaction of Ang 1 with the Tie2 receptor on endothelial cells. PDGR (platelet-derived growth factor) induces recruitment of smooth muscle cells. Angiopoietin (Ang) 2 is involved in the remodeling process by blocking the stabilizing action of Ang

Question 35

What is the function of ANG 2?

Answer 35

Destabilizes vessels in the third step of angiogenesis

Question 36

What is the function of VEGF?

Answer 36

Increase the permeability of vessels in the first step of angiogenesis

Question 37

What is the function of metalloproteases?

Answer 37

Enzymes that degrade the basal lamina in the second step of angiogenesis

Question 38

What is the function of plasminogen activator?

Answer 38

Disrupts the intercellular junctions of the basal lamina in the second step of angiogenesis

Question 39

What is the precursor for the formation of vessels?

Answer 39

Capillary tubes formed by endothelial cells

Question 40

What is the function of TGF-beta

Answer 40

Elaborates the basal lamina of newly formed capillary tubes

Question 41

What is the function of ANG-1?

Answer 41

Stabilizes newly forming vessels

Question 42

What is the function of FGF-2?

Answer 42

Works with VEGF and causes unstable vessel endothelial cells to prolifeerate and migrate to the signal

Question 43

What is the function of tie2 receptor?

Answer 43

Expressed on the surface of endothelial cells, and binds to ANG-1 This then recruits smooth muscle cells or pericytes

Question 44

Is proangiogenesis or antiangiogenesis used for: MI?

Answer 44

Pro

Question 45

Is proangiogenesis or antiangiogenesis used for:peripheral ischemia?

Answer 45

Pro

Question 46

Is proangiogenesis or antiangiogenesis used for:tumor growth and metastases?

Answer 46

ANti

Question 47

Is proangiogenesis or antiangiogenesis used for: ocular nerve neovascularization?

Answer 47

Anti

Question 48

Is proangiogenesis or antiangiogenesis used for:birth control?

Answer 48

anti

Question 49

Is proangiogenesis or antiangiogenesis used for: transplantation of islets of langerhands?

Answer 49

pro

Question 50

Is proangiogenesis or antiangiogenesis used for: reconstruciv surgery?

Answer 50

Pro

Question 51

Is proangiogenesis or antiangiogenesis used for: would healing?

Answer 51

pro

Question 52

Is proangiogenesis or antiangiogenesis used for: atheroscleotic plaque neovascularization?

Answer 52

Anti

Question 53

Is proangiogenesis or antiangiogenesis used for: hemangiomas?

Answer 53

anti

Question 54

Is proangiogenesis or antiangiogenesis used for: cerebral ischemia?

Answer 54

Pro

Question 55

Is proangiogenesis or antiangiogenesis used for: DM ulcers?

Answer 55

Pro

Question 56

What is tumor endothelial marker 8? What is its clinical significance?

Answer 56

Chemical expressed only by tumor cells. Allows for targeting of these tumors via antiangiogenesis

Question 57

Why is the great saphenous vein used in CABGs?

Answer 57

Its tunica media is much thicker than other veins d/t two muscle layers

Question 58

What happens to the great saphenous vein after it is used for a CABG?

Answer 58

undergoes thickeing