GI 4B- Anatomy, Physiology and Pathology of the Small Intestines 2

Question 1

Who is involved with emulsification?

Answer 1

Bile and lecithin

Question 2

What is emulsification?

Answer 2

Breaking up a large fat droplet into smaller fat droplets by bile acids

Question 3

Intestinal cells absorb lipid micelles and repackage them into a protein coated structure called______

Answer 3

Chylomicrons

Question 4

chylomicrons enter the lymphatic circulation they are transported upward through the _____ duct

Answer 4

thoracic

Question 5

The lymph ducts are emptied into the _____ veins

Answer 5

subclavian

Question 6

______ usually occurs within an hour after eating a fatty meal.

Answer 6

Lipemia

Question 7

This enzyme hydrolyzes the TGs of chylomicrons into fatty acids and glycerol

Answer 7

lipoprotein lipase

Question 8

What are the five general classes of lipoproteins

Answer 8

1. Chylomicrons
2. VLDL
3. IDL
4. LDL
5. HDL

Question 9

Chylomicrons are synthesized by the enterocytes of the __________ while VLDL, LDL, IDL, and HDL are synthesized by the ________

Answer 9

small intestines, liver

Question 10

How are lipoproteins named?

Answer 10

according to their ultracentrifugation and separated by their density

Question 11

What are the only lipoproteins monitored clinically to screen for atherosclerosis, MI and stroke risk

Answer 11

LDL-C and HDL-C

Question 12

What is the role of LDL

Answer 12

transport cholesterol and other lipids from the liver to the peripheral tissues making them available for membrane or steroid hormone synthesis

Question 13

What is the function of HDL

Answer 13

transport excess cholesterol from peripheral tissues to the liver where it is broken down and becomes part of the bile

Question 14

What drugs are used to treat elevated levels of LDL-C

Answer 14

‘statin’ drugs

Question 15

What are the adverse effects of statins

Answer 15

1. Myopathy- generic term for muscle disease
2. Myalgia- muscle pain or weakness
3. Rhabdomyolysis- very high serum creatine, often with dark urine and myoglobinuria

Question 16

What are risk factors for statin drug use

Answer 16

elderly, small size, high dose, liver or renal disease, diabetes, uncontrolled hypothyroidism, and interacting medications

Question 17

What vitamin is used to treat high cholesterol

Answer 17

Niacin (B3)

Question 18

Three basic preparations of Niacin

Answer 18

1. Immediate release
2. Sustained/ extended release
3. No flush

Question 19

Which niacine is worthless

Answer 19

no flush niacine

Question 20

What effects does niacin have on cholesterol levels

Answer 20

Niacin reduces the production of VLDL which leads to a secondary reduction in LDL. Niacin is also the most potent agent for raising HDL levels.

Question 21

Intolerance to niacin is common or uncommon?

Answer 21

common

Question 22

What hypolipidemic drugs are oldest and considered the safest

Answer 22

bile acid binding resins

Question 23

Resins bind bile acids in the intestinal lumen- this leads to two things:

Answer 23

1. decreased emulsification of dietary fat
2. Prevention of bile acid reabsorption (via enterohepatic circulation) this causes the liver to increase its production of bile acids, using hepatic cholesterol to do so

Question 24

Plasma LDL levels can be reduced ____% with maximal dose

Answer 24

30

Question 25

side effects to bile acid binding resins

Answer 25

constipation, bloating, flatulence, vomiting, anal leakage

Question 26

Resins bind many other drugs and interfere with their absorption:

Answer 26

fat soluble vitamins, folate, Thiazides, tetracyclines, propanolol, penicillin, warfarin FFTTPPW

Question 27

Water absorption is stimulated by _____ moving into the intestines

Answer 27

solutes

Question 28

Most K+ is absorbed passively when luminal [K+] rises because of absorption of water

Answer 28

solvent drag

Question 29

What regulated calcium absorption in the duodenum and jejunum

Answer 29

vitamin D3

Question 30

What does vitamin D3 stimulate in enterocytes to enhance calcium absorption

Answer 30

calbindins