Vasculature II

Question 1

What is present at junction of endothelial cells

Answer 1

intracellular junction

either ZO or interrupted incomplete fascia occludens. One cell with have marginal fold

Question 2

Why do pinocytotic vesicles have a large volume

Answer 2

tight junctions

vesicles can fuse, forming continuous temporal channels which allows for movement from lumen to ECM

Question 3

How to tell if it’s a continuous capillary

Answer 3

junctional complex (dark line) with marginal fold covering connection
lots of pinocytotic vesicles

Question 4

How to tell if it’s a fenestrated capillary w/o diaphragms

Answer 4

lots of fenestrations

Question 5

Where are fenstrated capillaries without diaphragms found

Answer 5

glomerular capillaries of kidney

Question 6

How to tell if it’s a fenestrated capillary with diaphragms

Answer 6

you can see the diaphragms

some pinocytotic vesicles, but not as many

Question 7

Where are fenestrated capillaries with diagpragms found

Answer 7

glomerular capillaries in kidney, elsewhere in kidney, intestines, endocrine organs

Question 8

How to tell if it’s a sinusoidal capillary

Answer 8

larger in diameter
huge pores
no basal lamina

Question 9

Where are sinusoidal capillaries found

Answer 9

bone marrow, liver, spleen, adrenal cortex

Question 10

Pericytic venules

Answer 10

bound in microcirculation, have pericytes

Question 11

Muscular venules

Answer 11

largger than percytic. Have smooth muscle in tunica media

Question 12

How to tell if it’s a pericytic venule

Answer 12

large lumen, thin wall

nuclei is dark blue, flattened

Question 13

Movement of lymphocyte

Answer 13

• Recognize adhesion molecules
• Attached to endothelium at region of marginal fold
• Disrupt junctional complex
• Moves between endothelial cell junction
• cross cell wall and enters ECM

Question 14

Small Vein

Answer 14

muscle in tunica media

Tunica adventitia collagen fibers thickest

Question 15

Medium vein

Answer 15

smooth muscle, elastic elements, and connective tissue present
connective tissue predominates

Question 16

Large vein

Answer 16

tunica adventitia contains lontiudinally arranged smooth muscle bundles
Thin tunica media
thick tunica adventitia

Question 17

Vaculogenesis

Answer 17

de novo vessel formation - make vessels from scratch

Question 18

Angiogenesis

Answer 18

growth from existing EC-derived channels

Question 19

Arteriogenesis

Answer 19

formation of arteries, arterioles, and collateral vessel remodeling

Question 20

Neovascularization

Answer 20

overaching term. Refers to vasculogensis, angiogenesis, and arteriogenesis

Question 21

Remodeling

Answer 21

vascular response to alterations in environment

Question 22

Endothelial precursor cells (EPC)

Answer 22

Bone marrow is the #1 source of this. Non-bone marrow niches exist and are mobilized in response to alterations in environment

Question 23

Function of vasculogenesis in adults

Answer 23

replace lost endothelial cells
re-endotheliazation of vascular implants
Neobascularization of ischemic organs, wounds, tumor

Question 24

Angiogenic steps

Answer 24

1) vasodilation (NO) and icnreased permeability
(VEGF)
2) degrade basal lamina by matrix metalloproteases and disrupt intercellular junction by plasminogen activator
3) ANG-2 destabilizes vessels
4) Migration and proliferation of endothelial cells mediated by VEGF and GFG
5) Form endothelial capillary tube
6) Elaboration of basal lamina by TGF-beta and recruitment of periendothelial cells mediated by ANG-1-TIE-2 and PDGF

Question 25

ANG-2

Answer 25

destabilizes

Question 26

ANG-1

Answer 26

stabilizes

Question 27

Vasodialation and increased permeability of vasculature

Answer 27

Endothelial cells attach to basal lamina and form junctional complexes with other endothelial cells NO and VEGF cause vasodilation and increased permeability

Question 28

Basal lamina disruption

Answer 28

matrix metalloproteases (MMPs) degrade basal lamina, separate it from endothelial cells

Question 29

Disruption of endothelial cell junction complexes

Answer 29

plasminogen activator disrupts interceullar endothelial cell junctions

Question 30

Proliferation and migration of endothelial cells

Answer 30

in presence of VEGF adn FGF-2, endothelial cells from pre-existing vasculature proliferate and migrate

Question 31

Formation of endothelial capillary tubes

Answer 31

Endothelial cells form capillary tubes, delicate precursor vessels

Question 32

Clinical Benefit of proangiogensis

Answer 32

myocardial, peripheral, and cerebral ischemia wound healing and fracture repair reconstructive surgery transplatation of islets of Langerhans

Question 33

Clinical benefit of antiangiogensis

Answer 33

``` tumor growth and metastases ocular neovascularization hemangiomas rhematoid arthritis atherosclerotic plaque neovascularization birth control ```

Question 34

What is different about great saphenous vein

Answer 34

tunica intima has endothelium plus basal lamina, subendothelium, poor developed IEM. tunica media has 2 or 3 muscle layers