Lecture 6 - Liver and Bile

Question 1

Functions of the liver

Answer 1

1. process nutrients
2. synthetic fxn
3. protection

Question 2

Glucose processing in the liver

Answer 2

• glycogenesis = storage via making of glycogen
• gluconeogenesis = making new glucose from propionate, lactate, AA
• glycogenolysis = breaking down glycogen
• FA synthesis

Question 3

Fat metabolism in the liver

Answer 3

• Synthesize triglycerides from:
  1. FA syn. in the liver
  2. FA mobilized from adipose tissue
• Lipoprotein synthesis = machinery for triglyceride transport

Question 4

Protein metabolism in the liver

Answer 4

• ammonia detoxification; urea and glutamine production
• non-essential AA synthesis

Question 5

Phenylketonuria (PKU)

Answer 5

caused by lack of enzyme that converts phenylalanine to tyrosine

Question 6

Synthetic fxn of the liver

Answer 6

• plasma protein synthesis
  1. albumin for transport of NEFA and creates osmotic pressure of plasma to keep H2O in blood
  2. fibrinogen, prothrombin for blood clotting
  3. transferrin for iron transport

Question 7

Protection fxn of the liver

Answer 7

1. prevent bacteremia via Kuppfer cells wthat line the sinusoids and are responsible for clearing infections
2. breakdown of toxins and hormones aka detoxifying and excreting in bile

Question 8

Where does liver damage occur

Answer 8

stellate cells produce fibrous scar tissue to wall off damaged areas to protect the liver
- a lot of fibrous scarring = sclerosis or cirrhosis

Question 9

Jaundice

Answer 9

• bilirubin is not excreted by hepatocytes in the liver
• yellow pigment; brown in feces

Question 10

3 causes of jaundice

Answer 10

1. haemolytic = too much lysis of RBC
2. hepatic = liver is damaged and not fxning properly
3. post-hepatic = bile trapped in gall bladder

Question 11

2 sources of blood to liver

Answer 11

1. oxygenated via hepatic artery from heart
2. deoxygenated via portal vein

Question 12

portal triad

Answer 12

portal vein, hepatic artery, bile duct

Question 13

hepatocytes

Answer 13

• heterogenous = different roles based on where in the sinosoid they are; metabolism, detoxification, protein synthesis

Question 14

space of disse

Answer 14

allows molecules through for hepatocytes to grab

Question 15

Kupffer cells

Answer 15

• line the hepatic sinusoids
• remove bacteria, immune complexes, and damaged erythrocytes

Question 16

What are bile acids synthesized from?

Answer 16

cholesterol

Question 17

primary bile acids

Answer 17

cholic acid and chenodeoxycholic acid (pk = 6)

Question 18

secondary bile acids

Answer 18

deoxycholic acid and litocholic acid

Question 19

What is added to secondary bile acids to make them conjugated bile acids

Answer 19

• glycine and taurine