Phys Bile Secretion and Gall Bladder Function Flashcards Preview

GI & Liver Fall 2013 CBD > Phys Bile Secretion and Gall Bladder Function > Flashcards

Flashcards in Phys Bile Secretion and Gall Bladder Function Deck (22):
1

Describe resting condition of biliary system

sphincter of Oddi is closed. Bile flows from liver to gallbladder, which expands.

2

contents of bile from liver

H2O
Ca++
K+
Cl-
Na+
Bile acids

3

contents of bile modified by secretin

adds:
HCO3-
Na+
H2O

4

What happens in gall bladder?

Removal of Na+, Cl-, HCO3-, H2O

5

CCK function

opens sphincter of Odi, contraction of gallbladder

6

How much of bile acid is lost in stool?

5%

7

Where is cholesteral/bile salts reabsorbed

ileum

8

How are bile salts reabsorbed?

K-dependent manner in ileum

9

2 primary bile acids & why is primary a thing?

Cholic acid
Chenodexoxycholic acid

Primary bile acids are synthesized by the liver & nowhere else.

10

2 secondary bile acids

deoxycholic acid (from cholic acid)
lithocholic acid (from chenodeoxycholic acid)

11

2 amino acids with which to make bile salts

glycine, taurine

12

why is it important to make a salt or an acid?

salt = hydrophilic/amphiphilic so stays in lumen
acid = more hydrophobic, so reabsorbed

13

How is bile salt synthesis regulated and by what enzyme?

bile salts returning in enterohepatic circulation are rate-limiting and inhibited by 7alpha-hydroxylase

14

choleretic effect

recirculation of bile salts to the liver stimulates biliary secretion

15

how are bile acids excreted?

facilitated diffusion from hepatocytes

16

how are bile salts absorbed from blood?

coupled to NaKATPase. BA/Na+ symporter.

17

How & where is hemoglobin broken down?

reticuloendothelial system. Then bilirubin is transported by albumin to liver.

In liver: bilirubin glucaronide (conjugated bilirubin) secreted into bile (yellow). In intestine bilirubin is unconjugated, converted to urobilinogen (by intestinal bacteria), then oxidized to urobilin and stercobilin (dark stool's color)

18

what gives urine a yellow/brown color?

urobilin (from urobilinogen of gut)

19

gallbladder removes what from bile?

NaCl & water

20

Most common type of gallstones

cholesterol stones, forms around nidus

21

10-20% of gall stones

pigment stones (unconjugated bilirubin)
gall bladder wall often damaged by bacteria & bile saturated by conjugated bilirubin

22

removal of gallbladder does what to bile plot?

levels it out - no high peak of bile to digest upon feeding