Flashcards in Vascular Disease 1- Leah (6)- Arteriosclerosis* Deck (53)
List the three layers of an arterial wall.
What are they comprised of?
1) intima, made up of endothelium (blood/ tissue barrier)
2)Media, made up of Muscle "M"
3) Adventitia, made up of CT, nerves, vasa vasorum
*adventitia is outermost*
Describe the function of the vasa vasorum:
Supplies blood to the outer 1/2 --> 2/3 of a vessel
List the four types of arteries:
3. small arteries (less than 2mm diameter)
Describe elastic artery properties.
Which arteries are classified as elastic?
-Large arteries that actively expand and contract (recoil) at systole and diastole
-Elastic, hence rich in elastic tissue
-Aorta and its large braches are elastic
Describe muscular arteries.
Which arteries are classified as muscular?
-rich in smooth muscle
1. smaller aortic branches (carotids)
3. renal vessels
Function of arterioles:
-transition blood from pulsatile --> steady state as enters capillary bed
-reduce pressure and velocity of blood
Describe makeup of capillaries: wall, diameter, xs surface area?
-made up of intima/ endothelial cells only
(lacks adventitia and media)
-diameter of a single RBC
(smallest individual vessel types)
-largest overall cross sectional area of all vessel tpyes
Preferred site of inflammation in vasculature?
post capillary venules
Describe structure of veins: lumen? wall thickness? special features?
-have valves to direct flow (loss of valves = venous insufficiency/ varicose veins)
Describe structure of wall (1) and function of lymphatic vessels (3):
- Thin walled, endothelium lined
- Fxn: drain interstitial fluid
-play a role in edema*
Normal function of endothelial cells in vessels (5):
-prevent thrombosis (maintain blood/ tissue interface)
-regulate immune/ inflammatory processes
-affect growth of other cells (mostly SMCs)
**Most "biochemically" active vascular cells**
Normal function of SMCs in vessels (3):
-synthesize ECM/ CT***
**Most "physically" active vascular cells.
How might tight endothelial junctions be loosened in the vasculature (2)?
What is the result?
-HTN or HISTAMINE most commonly loosen tight junctions.
-Result: EDEMA--> loss of leukocytes, proteins, and/or electrolytes
Basic definition of activation and dysfunction of endothelial cells:
Gaining some inducible property
(activation - good property; dysfunction- bad property)
*Not easy to distinguish the two processes, not testable
Describe abilities that an endothelial cell may gain during activation (4)
-production of adhesive molecule
Describe abilities that an endothelial cell may gain during dysfunction:
adhesive/ thrombogenic properties
List three disease processes that involve endothelial cell dysfunction:
Describe three events that may lead to vascular smooth muscle injury:
1. mechanical (angioplasty)
2. immunologic (i.e. transplant arteriosclerosis)
3. multifactoral (atherosclerosis)
"neointimal formation" may be used to describe?
"new intima" --> intimal thickening; a response to injury
Result of intimal thickening:
some stenosis and occlusion, but less so than atherosclerosis
What are three steps of intimal thickening after injury is induced?
1) recruitment of SM--> intima either from adjacent tissue or circulating precursors
2) SMC mitosis and proliferation
3) SMC elaborate intimal ECM; create new CT
Compare and contrast SMCs in normal vasculature vs during intimal thickening
-During intimal thickening, SMCs are in a *PROLIFERATIVE* state, located in the intima
-In a normal vessel, SMCs are in a *CONTRACTILE* state, located in the media
What are three types?
"Hardening of the arteries"- blanket term that includes:
3- Monckeberg medial sclerosis
Arteriolosclerosis effects what vessels?
What are the causes of arteriolosclerosis?
-small arteries and aterioles (usually renal)
-caused by HTN and DM
What are two types of arteriOLOsclerosis?
What are their causes?
(mild chronic HTN, DM)
-HYPERPLASTIC thickening/ onion skinning
Monckeberg medial stenosis:
What is it and in what population is it observed?
- benign ring calcifications found in muscular arteries
- media layer
- elderly population
- may be palpable or visible on Xray (pipestem appearance)
- Does NOT lead to occlusion of vessels
*Common benign finding on mammogram*
Cause of 50% deaths in the western world?
Atherosclerosis effects what types of arteries?
Who gets atherosclerosis?
-Atherosclerosis = elastic and muscular
-ArteriOLOsclerosis = aterioles and small arteries
*Old men + post menopausal women, esp w. genetic risk*
Function of LDL and HDL
LDL (bad): transports cholesterol to tissue
HDL (good): transports cholesterol out of tissue and into the liver for biliary excretion