Term
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Definition
An elevation of one or more of the following: cholesterol, cholesterol esters, phospholipids, or triglycerides (TG) |
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Term
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Definition
Lipid and protein complexes that transport cholesterol, triglycerides, and phospholipid
We usually call them "lipids" |
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Term
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Definition
Large TG-rich lipoproteins which deliver TG to adipose tissue or skeletal muscle
Synthesized from fatty acids or dietary triglycerides and cholesterol and bile acid (why lipid panel needs to be fasting) |
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Term
How are chylomicrons broken down? |
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Definition
Catabolized by lipoprotein lipase (LPL) which forms chylomicron remnants
Taken up by the liver to free cholesterol intracellularly TG converted to free fatty acids, apolipoproteins, or phospholipids |
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Term
List 5 types of lipoproteins |
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Definition
1. Chylomicrons 2. VLDL 3. LDL 4. HDL 5. Apolipoproteins |
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Term
Define VLDL (very low density lipoproteins) |
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Definition
Formed in the liver and intestine Carries 15-20% total serum cholesterol and most of the TG Precursor to LDL |
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Term
Define LDL (low density lipoprotein) |
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Definition
Formed from VLDL catabolism by LPL and hepatic lipase (HTGL)
Carries 60-70% total serum cholesterol Greatest contributor to atherosclerosis |
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Term
How are lipoproteins identified? |
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Definition
By the density of the lipoprotein- protein is more dense than fat |
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Term
What properties are unique to LDL? |
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Definition
-More artherogenic -Longer half life -More easily oxidized |
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Term
What is the purpose of LDL? |
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Definition
To carry cholesterol from the liver to organs that need it |
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Term
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Definition
Interaction with LDL receptors in liver triggers degradation |
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Term
What feedback changes occur with high intracellular LDL? |
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Definition
1. Inhibition of HMG-CoA reductase 2. Decreased LDL receptors 3. Increased storage of intracellular cholesterol 4. Increased excretion into bile portion of stools |
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Term
Give the Freidwald equation to calculate LDL |
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Definition
LDL= TC- (HDL+TG/5)
If triglycerides >400, this equation is inaccurate |
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Term
What is the primary role of HDL? |
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Definition
Reverse cholesterol transport:
Removes excess systemic and peripheral cholesterol (coronary arteries) and delivers it to liver for uptake and excretion |
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Term
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Definition
Proteins on outside of lipoprotein particles, provides structure, activates enzymes, and binds with cell receptors |
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Term
What is ApoA associated with? |
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Definition
HDL and chylomicrons
(Good ones) |
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Term
What is ApoB associated with? |
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Definition
LDL, VLDL, IDL, and chylomicrons
(Bad ones) |
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Term
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Definition
Lipoprotein lipase
In fat and muscle, hydrolyzes TG, chylomicrons, and VLDL & releases free fatty acids (which are stored as fat or used for energy) |
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Term
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Definition
Hepatic lipase
Converts VLDL to LDL by removing TG from VLDL |
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Term
What is the role of Lecithin-cholesterol acyl transferase (LCAT)? |
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Definition
Allows HDL to collect cholesterol |
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Term
What is the role of Cholesterol ester transfer protein (CETP)? |
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Definition
Involved in the exchanges of cholesterol between TG and HDL |
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Term
What lipoproteins are elevated in type I dyslipidemia? |
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Definition
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Term
What lipoproteins are elevated in type IIa dyslipidemia? |
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Definition
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Term
What lipoproteins are elevated in type IIb dyslipidemia? |
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Definition
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Term
What lipoproteins are elevated in type IV dyslipidemia? |
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Definition
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Term
What lipoproteins are elevated in type V dyslipidemia? |
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Definition
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Term
What lipoprotein phenotypes associated if a patient has high triglycerides? |
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Definition
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Term
What lipoprotein phenotypes associated if a patient has high cholesterol? |
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Definition
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Term
List five disease secondary causes of hypercholesterolemia |
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Definition
Hypothyroidism
Obstructive liver disease
Nephrotic syndrome
Anorexia nervosa
Acute intermittent porphyria |
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Term
What drugs can cause secondary hypercholesterolemia? |
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Definition
Progestins, thiazide diuretics, glucocorticoids, β-blockers, isotretinoin, protease inhibitors, cyclosporine, mirtazapine, sirolimus |
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Term
List disease secondary causes of hypertriglyceridemia |
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Definition
Obesity Diabetes mellitus Lipodystrophy Glycogen storage disease
Ileal bypass surgery Sepsis Pregnancy Acute hepatitis Systemic lupus erythematosus Monoclonal gammopathy: multiple myeloma, lymphoma |
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Term
What drugs can cause secondary hypertriglyceridemia? |
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Definition
Alcohol, estrogens, isotretinoin, betablockers, glucocorticoids, bile-acid resins, thiazides; asparaginase, interferons, azole antifungals, mirtazapine, anabolic steroids, sirolimus, protease inhibitors |
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Term
List 6 disease causes of secondary hypocholesterolemia |
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Definition
Chronic liver disease Malnutrition Malabsorption Myeloproliferative diseases Chronic infectious diseases: AIDS, tuberculosis Monoclonal gammopathy |
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Term
List disease causes of low HDL |
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Definition
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Term
List drugs that can cause secondary low HDL |
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Definition
Non-ISA β-blockers, anabolic steroids, probucol, isotretinoin, progestins |
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Term
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Definition
Plaques that form in medium and large arteries that contain lipids, inflammatory cells, smooth muscle cells, and connective tissue.
In most, the underlying cause of CAD and ACS |
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Term
List the five vessel wall components |
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Definition
1. Endothelium 2. Basement membrane 3. Elastic tissue 4. Collagen 5. Smooth muscle |
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Term
What is the function of the endothelium in the vessel wall? |
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Definition
Regulates blood flow and active transport of circulating substances throughout the cytoplasm |
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Term
What is the function of the basement membrane in the vessel wall? |
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Definition
Transport barrier and membrane support |
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Term
What is the function of the collagen in the vessel wall? |
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Definition
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Term
What is the function of the smooth muscle in the vessel wall? |
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Definition
Arterial metabolism and active contraction, facilitates entry of lipoproteins |
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Term
What are the three layers of the vascular system, from inside to outside? |
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Definition
1. Intima 2. Media 3. Adventita |
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Term
What are the effects of aging on the vascular system? |
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Definition
Increase in intimal thickness, rigidity
Accumulation of smooth muscle cells, connective tissue, and cholesterol
This leads to vasoconstriction, thrombosis, and inflammation- which promotes atherosclerosis |
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Term
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Definition
Systemic increase in vein thickness, primarily affects lower extremity veins that are exposed to stasis and increased luminal pressure |
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Term
List Risk factors for atherosclerosis |
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Definition
•Age •Cigarette smoking •Hypercholesterolemia •Lifestyle •Family HIstory •Hyperhomocysteinemia •Oxydized LDL •Mechanical injury to the endothelium •Immunologic attack •Infection induced |
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Term
What is the response to injury hypothesis |
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Definition
Injury to endothelium increases LDL transport and retention in intima
LDL binding to extracellular matrix increases its "residence time"
LDL changes via oxidation to cause an inflammatory response, which increases plasminogen, coagulation, and endothelin. Foam cells form, "fatty streak" |
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Term
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Definition
Develops into a lesion after repeated injury and repair within an atherosclerotic plaque
Leads to a fibrous cap protecting the underlying lipid core, collagen, and inflammatory cells
Maintenance of the fibrous cap is critical to prevent rupture and consequent thrombus |
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Term
What are outcomes of plaque rupture? |
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Definition
A clot forms on the top of the ruptured plaque Produces either a complete or incomplete occlusion of the lumen
This can cause angina, stroke, MI, death, PAD, arrhythmias, abdominal aortic aneurism |
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