Bile Secretions/Large Intestine Flashcards Preview

S&F IV: Exam One > Bile Secretions/Large Intestine > Flashcards

Flashcards in Bile Secretions/Large Intestine Deck (16):
1

Bile Salts

Addition of Na+ to bile acid; form cylindrical micelles to contain FAs, cholesterol, monogylcerides, etc.

2

Bile Pigments

Bilirubin; soluble when conjugated in the liver and secreted from liver as salt glucuronide

3

Bile Salt Reabsorption

Bile salts initially actively reabsorbed in the terminal ileum

Reabsorbed into liver from portal blood by Na+-cotransport and secreted across apical membrane via ATPase-dependent bile pump

*Reabsorption from portal blood dependent upon activity of Na+/K+-ATPase

4

Bile-independent fraction of biliary secretion

Influenced by activity of secretin

(Increases HCO3- and water)

5

Bile-dependent fraction of biliary secretion

Amount of bile secreted is directly related to the amount of bile reabsorbed

*Example: Increased secretion => Increased return => Decreased synthesis

6

Actions of CCK on gall bladder (2)

1. Contracts smooth muscle

2. Relaxes sphincter of Oddi

7

Cholelithiasis

A. Cholesterol (more common)
-Ppt. of cholesterol due to supersaturation

B. Pigment
-Unconjugated bilirubin ppts. w/ Ca2+

8

Cholecystectomy

Performed for the treatment of gallstones; bile will empty slowly and continuously into the duodenum since there is no place for storage

*High-fat meals should be avoided

9

Most common contraction in colon

Segmentation; partly responsible for appearance of haustra

10

Rectal contractions

Segmental contractions greater here than in sigmoidal colon

=> Retrograde movement of fecal matter

11

Rectosphincteric reflex

Contraction of the rectum and relaxation of the internal anal sphincter in response to fecal matter being forced into the rectum

12

Hirschsprung's Disease

Absence of inhibitory enteric nervous system in a part of the colon resulting in tonic constriction

=>Accumulation of contents proximal to this constriction causing severe constipation

Treatment= removal of segment of colon

13

Responsible for movement of fecal material into the rectum

Mass movement

14

Primary Bile Acids

Produced by the liver from cholesterol; primarily cholic and chenodeoxycholic acids

15

Reabsorption of deconjugated bile acids

Passive

-Could be deconjugated by intestinal flora

16

Changes in colonic fnxn w/ Constipation

1. Increased storage capacity of colon

2. Decreased propulsive capacity of descending and sigmoidal colon