Lipid and Lipoprotein Metabolism Flashcards Preview

Med Lab Test 2 > Lipid and Lipoprotein Metabolism > Flashcards

Flashcards in Lipid and Lipoprotein Metabolism Deck (37):
1

What are the clinically important lipids?

1. Cholesterol 2. Trigylercides (phospholipids and glycolipids also exist).

2

Fats are INSOLUBLE in...

water and plasma

3

What are some examples of the functions of lipids?

Steroid hormone precuros, bile salt precursor, cell membrane components, provides energy and metabolic fuel, insulation, provides maturity to fetal lung as pulmonary surfactant.

4

What is cholesterol an essential component of?

cell membranes

5

What is cholesterol a precursor for?

steroid hormones; bile salt synthesis

6

How is lipid stored in adipose tissues? (what form?)

Triglycerides

7

What are some functions of trigylcerides?

main storage form in man, cushions vital organs, provides insulation, acts as metabolic fuel and energy source.

8

What do phospholipids "act as"?

biologic detergents, and stabilizers.

9

What is the chemical structure of phospholipids?

Hydrophilic head, and hydrophobic tail

10

What are some functions of phospholipids in the body?

surfactant in lungs (phosphatidylcholine), and protects against premature infants. It also stabilizes cell membranes.

11

What do glycolipids contain?

contain carbohydrate

12

What is the function of glycolipids?

major lipid of cell membranes in the brain and CNS (gangliosides and sphingomyelin).

13

What are the sources of lipids?

1)exogenous (dietary intake, 300-500 mg chol/day), chylomicrons. 2) endogenous (synthesized by liver, 1500 mg chol/day, VLDL)

14

How do lipids get packaged to travel through physiological fluids?

lipoproteins

15

What are the specific proteins that are on lipoproteins surface?

apolipoproteins

16

apolipoproteins do what?

activate metabolic enzymes, maintain structural integrity of lipoprotein, facilitate uptake of lipoprotien into cells.

17

What does research show about apolipoproteins?

abnormalities may lead to abnormal lipid metabolism and metabolic disorders such as: atherosclerorsis, CV disease, stroke, Alz. disease

18

Lipoprotein classifications:

chylomicrons, VLDL, LDL, HDL. They are classified based on relative densities. Chylos float, HDLs sink!

19

Which of the following lipoproteins carries the highest percentage of cholesterol?

LDLs

20

Which of the following lipoproteins carries the highest percentage of triglycerides?

BOTH chylomicrons (carries exogenous, found in non-fasting state) and VLDL (carries endogenous, found in fasting state )

21

What causes the plasma to appear lipemic?

VLDL, will make plasma look hazy

22

Where does LDL deposit cholesterol?

plaques

23

Increased LDLc increases risk of...

CHD

24

Which of the following lipoproteins carries the highest percentage of protein?

HDL

25

Which of the following lipoproteins carries the highest percentage of phospholipid?

HDL

26

What patient preparations are necessary for sample collection of a lipid panel?

12-14 hour overnight fast to clear system of chylomicrons. Collect in GLYCEROL-FREE tube.

27

What are factors that affect cholesterol levels? (see slides 25 and 26 of lipids for EXACT info)

age (increases), sex (different trends for female vs male--see chart), menustration (peaking effect), fasting (negligible), stress (increases), time of specimen (variable), hemolysis (negligible)

28

What is a lipid profile?

Used to assess patient risk of CHD. Gives you
1. total cholesterol 2. total triglyceride 3. HDL 4. LDL 5. Cholesterol:HDL ratio

29

How do you calculate LDLc?

Friedwald equation.

LDLc= Total Cholesterol -HDL-VLDL.
VLDL= tri-g's/5

30

what should your total cholesterol be?

less than 200

31

what should your HDL be?

35-55 (you want it high)

32

what should your LDL be?

less than 130

33

what should your tri-g's be?

less than 150

34

What are risk factors for CHD?

male older than 45 (females older than 55), fam hx, smoking, hypercholestermia: LDL more than 160 with less than 2 risk factors or LDL 130-159 with more than 2 risk factors, obesity sedentary lifestyle, hypertension, stress, diabetes

35

What are some causes of secondary hyperlipidemia and dyslipprotenemia?

drugs, alcohol, obesity, DM, hypopituitarism, Hypothryroidism, pregnancy, lipid storage diseases, renal disease, heptic disease, acute or transient conditions, anorexia nervosa, SLE, Gout

36

What is Tangier's disease?

increased catabolism of the HDL molecule. Results in severely decreased or absent HDL with accumulation/deposits of cholesterol in tissues and vital organs. You get a big liver, increased risk of CHD, and plasma cholesterol is low

37

What are lipid storage disorders

critical lysosomal enzyme needed for lipid catabolism is decreased, absent, or defective. Results in accumulation of lipid in lyzosomes of vital organs and tissues. Often fatal at early age