Lipids & Lipoproteins Flashcards
A genetic problem causing decreased elimination of VLDL
Hyperlipoproteinemia IV (Familial hypertriglyceridemia)
A delay in removal of LDL due to a lack of high affinity LDL-Apo B receptors in peripheral tissues
Hyperlipoproteinemia IIa (Familial hypercholesterolemia)
In the more common form of HLP IIa the people tend to live into their 50’s or so, while in the more rare form they usually don’t make it to 20. ____ occurs in 1/500, while _____ occurs in 1/1 million
Heterozygous, homozygous (autosomal dominant)
SSx’s of which type of hyperlipoproteinemia?
- Xanthelasmas and xanthomas
- Arcus juvenilis (premature white/gray ring in corneal margin)
- arterial bruits
- claudication (pain, usually in legs, caused by too little blood flow (PAD))
- accelerated atherosclerosis
Type IIa
Name the 4 SSx’s of HLP IV
- Obesity
- Lipemia retinalis (abnormal appearance of retinal arteries and veins)
- Atherosclerosis
- Hepatosplenomegaly
Which type of HLP results in increased triglycerides and decreased HDL, along with normal cholesterol and LDL levels?
Type IV
What are the major lab findings in HLP IIa?
- Increased serum cholesterol
- Increased LDL (“bad guy”)
- TG normal
In the _____ form of HLP IIa, serum cholesterol is usually increased to levels of 250-500mg/dL, while the _____ form has levels increased to 500-1,200mg/dL
Heterozygous, homozygous
The protein fraction of lipoproteins is composed predominantly of several polypeptides called _____
Apoproteins
____ are considered to be an accurate predictor of CHD
Lipoproteins
___ are proteins in the blood whose main purpose is to transport lipids, triglycerides, and other insoluble fats.
Lipoproteins
What are the four categories of lipoproteins?
- Chylomicrons
- HDL
- LDL
- VLDL
Which two lipoproteins are mainly triglycerides?
- Chylomicrons
2. VLDLs
Which lipoprotein is considered the “bad guy” because it is mainly composed of cholesterol?
LDLs
HDLs are predominantly composed of _____
Protein
___ are primarily triglyceride transport vehicles
Chylomicrons
Where do chylomicrons originate?
Intestinal epithelial cells
The liver clears chylomicrons from the blood, incorporates the triglycerides into lipoproteins, and releases them back into the bloodstream as ____
VLDLs
The alpha-lipoprotein
HDL
This lipoprotein is made in the liver and carries cholesterol in the bloodstream from the tissues TO the liver (reverse cholesterol transport)
HDLs
The ___/TC ratio should be at least 1:5, with an ideal ratio being 1:3.
HDL
HDLs are composed of ___% protein, 1-5% TG, ___% cholesterol, and 30% phospholipid
50%, 15%
Reference values for HDL? Both sexes.
Men: >40mg/dL
Women: >46mg/dL
What level of HDLs is considered protective against heart disease?
> /=60mg/dL
Increased HDLs is called?
Hyperalphalipoproteinemia
High HDLs is considered a good thing, but in ____ disease they will also be increased.
Chronic liver disease
Uncontrolled diabetes, hepatocellular disease, chronic renal failure, nephrosis, uremia, cholestasis are all complications that would ____ HDL levels
Decrease (i.e. bad.)
What type of things can increase HDL levels?
Exercise, weight loss, estrogens, insulin, hypothyroidism
The beta-lipoprotein
LDL
____ carry cholesterol TO the peripheral tissues and their levels are directly proportional to the risk of CHD
LDLs
LDLs are composed of ___% cholesterol
45%
Friedewald Equation: ___=TC-(HDL + TG/5)
LDL
The formula for calculating LDLs is only valid for TG levels
400
Reference range for LDLs? (Normal)
<130mg/dL
Optimal levels of LDLs?
<100mg/dL
LDL levels >/=___ are considered very high
190mg/dL
Which type of hyperlipoproteinemia results in increased LDLs?
HLP IIa (familial hypercholesterolemia)
Hyperthyroidism and chronic anemia may cause ___ levels of LDL
Decreased
The primary carriers of transporting triglycerides from the liver to other organs?
VLDLs
VLDL levels in excess of __-__% are associated with an increased risk of coronary disease.
25-50%