Exam 2: Ch 18 Blood Vessel Disorders & Cholesterol

Question 1

3 layers of a blood vessel

Answer 1

tunica externa

tunica media (smooth muscle activity)

tunica intima (only layer capillaries have)

Question 2

endothelial cells

Answer 2

simple squamous epithelium that lines cardiovascular system

maintains selectively permeable barrier in brain

regulates clotting, inflammation, vessel reactivity

influences growth of smooth muscle

Question 3

how do endothelial cells regulate clotting

Answer 3

produces thrombogenic factors and prevents platelet adhesion

Question 4

how do endothelial cells regulate vessel reactivity

Answer 4

produce dilators (NO)

produce constrictors (ACE)

Question 5

endothelial dysfunction (plaques)

Answer 5

reversible changes in response to environmental stimuli

modulate blood flow (NO, ACE)

regulate SMC proliferation (growth factors)

regulate inflammation (produce IL)

Question 6

vascular SMCs

Answer 6

can constrict and relax

synthesize collagen

migrate and proliferate

Question 7

lipids are transported in the blood as…

Answer 7

lipoproteins

chylomicrons: carry triglycerides and cholesterol from intestine to tissues and liver

VLDL: main carrier of triglycerides

LDL: main carrier of cholesterol

Question 8

hypercholesterolemia means

Answer 8

high blood lipids

risk factor for MI and stroke

Question 9

VLDL

Answer 9

made in liver from cholesterol

deliver triglycerides to tissues…becomes cholesterol rich IDL

Question 10

lipoprotein and apoprotein structures

Answer 10

micelles

hydrophilic outside, hydrophobic core

Question 11

apolipoproteins

Answer 11

Proteins that bind lipids

control fate of lipids b/c receptors

activate enzymes for lipoprotein metabolism (remove lipids from lipoproteins)

recognized by tissue cell receptors – endocytosis takes in lipoproteins

Question 12

chylomicrons

Answer 12

synthesized in cells of sm. intestinal wall

Carry dietary triglycerides and cholesterol from intestines to tissues and liver

Exogenous pathway

Question 13

exogenous lipid transport

Answer 13

chylomicrons transfer triglycerides to cells for storage and energy use

remnant (cholesterol rich) chylomicrons taken up by liver

cholesterol used to make VLDL or is excreted in bile acid

Question 14

the liver makes and releases ____ & _____

Answer 14

VLDL, HDL

Question 15

endogenous lipid transport

Answer 15

VLDL delivers triglycerides to tissues, turns into cholesterol rich IDL

IDL recycled to VLDL by liver or to LDL in circulation

LDL in blood taken up by LDLr if low

LDL scavenged by macrophages and monocytes in tissues and into blood vessel walls if high –> plaque

Question 16

low LDLr leads to

Answer 16

high circulatory LDL –> plaque

Question 17

HDL

Answer 17

returns cholesterol from peripheral tissues to the liver…requires ABCA1

exercise increases HDL

smoking decreases HDL

Question 18

ABCA1

Answer 18

ATP binding cassette transporter A, class 1

transports cholesterol out of vessel wall cells

genetic defect = Tangier disease (low HDL)

Question 19

a low HDL is indicative of

Answer 19

early atherosclerosis

Question 20

type 1 familial hyperchylomicronemia is high in..

Answer 20

french-americans

high chylomicrons means deficiency in LPL (lipoprotein lipase) or apo cells

Question 21

hypercholesterolemia diagnoses and causes

Answer 21

Dx: LDL based on fasting blood sample every 5 yrs (20+ older)

causes: deit, co-morbidities like diabetes mellitus, meds, genetics

Question 22

calculate total cholesterol

Answer 22

LDL + HDL + tF/S

Question 23

genetic basis of hypercholesterolemia

Answer 23

LDLr gene abnormality

heterozygoes have LDLs of 250-500 mg/dl (1st heart attack in 30s)

homozygotes have LDLs of ~1000 mg/dl (see fat in blood)

xanthomas and atherosclerosis common

heart attack in 20s

Question 24

treatment of hypercholesterolemia

Answer 24

not based on LDL goals

risk reduction

statins

Question 25

how do statins work

Answer 25

higher intake of LDL causes it to decrease less cholesterol production in liver causes higher LDL receptors

Question 26

ASCVD

Answer 26

atherosclerotic cardiovascular disease

Question 27

how are statins perscribed

Answer 27

moderate to high for people with clinical ASCVD no ASCVD but LDL > 190 mg/dl DM w/o ASCVD regardless of LDL or 10-yr risk 10-yr risk > 7.5% regardless of LDL, DM

Question 28

other CHD risk factors

Answer 28

smoking HTN low HDL DM

Question 29

non modifiable CHD risk

Answer 29

family history age males > 45 females > 55 (post-menopausal)

Question 30

diet therapy for cholesterol

Answer 30

lower calories, sat fat, cholesterol higher fruits, veggies, fish used for 3 months before starting meds

Question 31

statins

Answer 31

HMG CoA inhibitors, block cholesterol syn. in liver --> upregulate LDLr bile acid resins bind bile acids in intestine nicotinic acid and fibrates block VLDL syn.

Question 32

heart attack and plaques

Answer 32

plaques lead to rupture clot forms at rupture site... hole in endothelium

Question 33

some artery locations are more likely to accumulate...

Answer 33

plaques

Question 34

atherosclerosis

Answer 34

Thickened artery wall due to plaque Preference for medium to large arteries --> CHD is one type fibrous plaques at ~20 take decades for disease to develop

Question 35

CHD death rates

Answer 35

low since 1960 but CHD remains #1 killer in US

Question 36

risk factors for atherosclerosis

Answer 36

hypercholesterolemia #1 HTN (stress injury to edothelium), smoking (chemical injury), obesity aging family history

Question 37

C-reactive protein

Answer 37

marker of systemic inflammation (CHD is an inflammatory process) anti-inflammatory effect so less plaque forms

Question 38

homocysteine

Answer 38

methionine metabolite in animal protein damages endothelium and stimulates clotting Vit B breaks down, but do not decrease risk

Question 39

lipoprotein A

Answer 39

Altered LDL Increases cholesterol delivery to injured blood vessels increases risk of CHD

Question 40

fatty streak

Answer 40

yellow lines in tunica intima of major arteries composed of SMC filled with cholesterol and macrophages --> foam cells (fatty macrophages present from ~20yr old

Question 41

fibrous plaque

Answer 41

fibrous cap over lipids and necrotic core reduce flow in vessel rupture and suddenly occlude vessel inhibition of NO by oxidized LDL lowers vasodilation

Question 42

what happens in fibrous plaques

Answer 42

LDL infiltrates to subendothelial space monocytes bind to site of endothelial injury and enter space to oxidize LDL (which is toxic to endothelium)

Question 43

what happens when LDL is oxidized by monocytes in fibrous plaques

Answer 43

rapid uptake by monocytes inhibition of NO release stimulation of cytokine release from T cells

Question 44

cytokine release in fibrous plaques stimulated by monocytes oxidizing LDL

Answer 44

activate monocytes to differentiate into macrophages SMC proliferation

Question 45

macrophages take up...

Answer 45

LDL to form foam cells

Question 46

SMC in fibrous plaques

Answer 46

lay down collagen in plaque take up LDL to form foam cells

Question 47

atherosclerotic occlusive disease (peripheral artery disease)

Answer 47

commonly affect lower extremities same risk factors as atherosclerosis...smoking really bad intermittent claudication

Question 48

intermittent claudication

Answer 48

pain when walking, atrophy of skin, blanching when leg elevated occurs when vessels > 50% occluded Dx. tibial:brachial systolic BP ratio less than .9, ultrasound, CT, MRI Rx. ASA, surgery, reduce CHD risk

Question 49

thromboangitis obliterans (Buerger disease)

Answer 49

vasculitis that causes thrombus formation effects medium sized arteries of foot and hand smoking and genetics Dx: similar to intermittent claudication Rx: stop smoking, sympathectomy

Question 50

Raynaud's disease

Answer 50

arterial vasospasm in arteries of fingers pallor and cold followed by hyperemia cause ulceration and gangrene

Question 51

Primary Raynaud's disease--no known cause

Answer 51

overactive SNS most common in healthy young women triggered by cold or strong emotion

Question 52

Secondary Raynaud's disease

Answer 52

Associated with previous vessel injury like frostbite Trauma from use of vibrating tools

Question 53

diagnosis of Raynaud's disease

Answer 53

cold to trigger

Question 54

treatment of Raynau's disease

Answer 54

eliminate triggers (cold) quit smoking calcium channel blockers alpha-blockers avoid stress