Lec 15

Question 1

What makes up majority of bile?

Answer 1

mostly water, then bile salts

Question 2

What is effect of bile on biliary flow?

Answer 2

more bile acids in biliary tree = better flow

Question 3

What are the 2 primary bile acids?

Answer 3

cholic acid, chenodeoxycholic acid

Question 4

How are primary bile acids synthesized?

Answer 4

synthesized in liver from cholesterol

rate limiting enzyme = 7 alpha hydroxylase

Question 5

What are the secondary bile acids?

Answer 5

deoxycholic acids and lithocholic acid

Question 6

How are secondary bile acids formred?

Answer 6

• conjugation of primary bile acid with AA glycine or taurine
• secreted in bile
• oxidized by intestinal bacteria

Question 7

What happens to bile salts in intestine?

Answer 7

70-80% reabsorbed in distal ileum and return to liver via portal vein

10-15% reabsorbed in colon after bacterial deconjucation

10-15% lost in feces

Question 8

What percent of bile salts in circulation are recirculated vs new?

Answer 8

> 95% recirculated

< 5% are from new synthesis

Question 9

What mediates gallbladder contraction?

Answer 9

CCK

Question 10

What are some of bile duct disease?

Answer 10

things get backed up; have cholestasis = bile standing still

• -> excess bile acids –> hepatocyte injury
• -> excess bilirubin –> jaundice
• -> excess cholesterol –> xanthomata

Question 11

What is the effect of ileal disease or ingestion of bile acid-binding resins [cholestyramine]

Answer 11

have insufficient reabsorption of bile acids

Question 12

What is the effect of bile acid depletion?

Answer 12

steatorrhea, gallstones

Question 13

What is the effet of bile acid free-flow into colon?

Answer 13

diarrhea

Question 14

What happens if you get bile acid accumulation in skin?

Answer 14

itching –> pruritis

Question 15

What are gallstones composed of?

Answer 15

bilirubin [pigmented]
cholesterol
both

Question 16

When do you get pigmented gallstones?

Answer 16

when high concentrations of unconjugated bilirubin in bile

due to hemolysis, liver disease, infected bile, starvation of total parenteral nutrition

Question 17

What are pigmented gallstones made of?

Answer 17

bilirubin and calcium = not crystals

Question 18

What is relationship acidity of gallbladder and likelihood of stone precipitation?

Answer 18

more acidic –> less likely to get stones

Question 19

When do you get cholesterol gallstones?

Answer 19

40, female, fat, fertile

Question 20

Where do cholesterol vs pigmented stones localize?

Answer 20

cholesterol stone = in gallbladder not ducts

pigmented = can arise in either gallbladder of bile ducts

Question 21

What is biliary colic?

Answer 21

stone stuck in cystic duct causes pain

Question 22

Are you more likely to get gallstone in fed or fasting state?

Answer 22

fasting

Question 23

What is acute cholecystitis?

Answer 23

cystic duct obstruction + infection

80% subside w/ antibiotics alone

Question 24

What can you give to dissolve cholesterol gallstones?

Answer 24

ursodeoxycholic acid = main constituent of bear bile; liquefies the bile

side effect = diarrhea

Question 25

What is biliary sludge?

Answer 25

history looks like biliary colic but may not have an actual stone yet