(43) Biliary Secretion

Question 1

(Species Differences: Biliary Tract Anatomy)

1. What species don’t have a gallbladder (continuously secreting)?
2. Canine?
3. feline?
4. pros and cons of gallbladder?

Answer 1

1. rat, horse, gopher, deer
2. single gallbladder
3. double gallbladder (many different forms)
4. pros: storage of bile salts

good for horses not to have one cause they need to eat all of the time

Question 2

(Species Differences: Biliary Ductal Anatomy)

check it out

feline has common bile duct

sometimes in cats with inflammatory bowel diease - it can lead to polengitis and pancreatits (these three go together a lot in cats basically)

Question 3

(Anatomic Units of Biliary Secretion)

(Several vessels to account for)

1. hepatic artery in black - transporting what into the liver? This blood is being transported where which makes it what?
2. Portal blood from the gut - also going where?
3. What type of bile flow?
4. Give me the order of bile flow (4 of them)
5. bile goes where for those who have storage? for those that don’t?

Answer 3

1. oxygenated blood; transported in to the center of the gland, making it centripedal
2. to the center
3. centrifugal blood flow
4. hepatocytes –> canaliculi –> ductules –> ducts
5. gallbladder; small intestine

Question 4

(Composition of Bile)

1. What account for 1/2 to 2/3 of total bile solutes?
2. Also contains water, electrolytes, cholesterol, phospholipids, bilirubin, hormones, and protein
3. What constituents are reabsorbed in the gallbladder? What happens to other constituents?
4. bilirubin accoutns for color

Answer 4

1. bile salts

2.

3. water and electrolytes; they are concentrated

Question 5

(Three Functions of Biliary Secretion)

1-3 name them

Answer 5

1. excretory route –> drugs and metabolites
2. HCO3 –> acid neutralization
3. Bile salts –> fat digestion and absorption

Question 6

(4 Components of Regulation of Biliary Secretion)

1-4. There are four - name them…

Answer 6

1. acetylcholine (gallbladder)
   - autonomic innervation - parasympathetic - feeding stimulatetes neural and hormonal activation - stimulates contraction and release of bile into small intestine
2. CCK (cholecystokinin)

contraction of gallbladder - relaxation of sphincter of Oddi

3. Secretin

bile - reduces acidity via HCO3 release

4. Bile Salts

bile salt return from intestine to the liver stimulate futher bile flow (bile salt dependent flow)

Question 7

(Cholesterol and Bile Acid Synthesis)

1. What kind of ring structure?
2. five or eight carbon side chain terminating in what?
3. Where are the hyrdoxyl groups located?

Answer 7

1. steroid 4-ring structure
2. carboxylic acid
3. C3, C7, C12

Question 8

more hydroxyl groups means more hyrdophilic

Question 9

(Conjugation of Bile Acids: Species Differences)

(these are secondarily conjugated in the small intestine)

(conjugated with taurine or glycine)

1. Dogs and cats conjugate primarily with what?
2. Dogs can convert to what?
3. Cats are obligate what?

Answer 9

1. taurine
2. glycine conjugation
3. taurine conjugators

Question 10

(Role of Bile Salts in Fat Digestion and Absorption)

1-2. What are the two roles?

3. What is the effect of emulsification?
4. bile salts are transported to where - where they are reabsorbed and sent to liver?

Answer 10

1. emulsification
2. micellarization
3. triglyceride –> (pancreatic lipase) –> monoglyceride + 2 ffa + glycerol

(learn this graph pretty well)

know that lacteal = intestinal lymphatics

can also go into portal capillaries - go into liver - redistributed into systemic circulation - DIFFERENCE in the ones going into portal - medium chain (c8-c12) - taken up preferentially into portal capillaries - short and long are taken up by lymphatic system (c4-8, c14-18)

lymphatic disease in dairy cow - Johne’s disease - sever wasting disease - infection and inflammation of that lacteal system - don’t get lipids moving from gut into circulation - wasting

dogs also get this - intestinal lymphanagia

so you solve these by feeding medium TGs that go through protal capillary

4. ileum (enterohepatic circulation)

(actually should look at this whole slide - its on the pad)

Question 11

(Enterohepatic re-ciculation of bile salts)

learn this bitch

Question 12

(Bile Acid - Induced Tissue Injury)

1-3. What three things can be injured by bile acid?

4. What occurs if the biliary duct is blocked?

Answer 12

1. stomach
2. esophagus (reflux esophagitis)
3. distal colon (colonic diarrhea)
4. accumulation of bile salts in the liver (hepatocyte apoptosis)

Question 13

(Integration of Function - Biliary, Pancreatic, and Intestinal Secretion)

1-3. What three ways are synergy achieved?

Answer 13

1. neural (cholinergic innervation of gallbladder (contraction to move bile salts into small intestine), duodenum, pancreas)
2. endocrine

secretin - stimulates pancreatic ductal cells to release HCO3- into intestine, also stimulates epithelial cells in intestine to release HCO3- (think there is a third here)

CCK - gallbladder contraction and relaxation of sphincter of Oddi

3. paracrine

bile salt effect on stimulation of bile flow

Question 14

(Questions to think about)

1-3. Name three clinical signs of biliary obstruction

Answer 14

1. weight loss (loss of lipid digestion - lipid malnutrition)
2. increased lipid in poo - smelly poo
   3a. jaundice
   3b. change in color of feces (bilirubin)

Question 15

(Questions to think about)

1. advantage