Biliary and Pancreatic Function - 122

Question 0

What are some uncommon causes of pancreatic disease?

Answer 0

Chronic pancreatitis
Pancreatic insufficiency
Autoimmune pancreatitis

Question 1

What are the most common pancreatic diseases?

Answer 1

Acute pancreatitis

Carcinoma of the pancreas

Question 2

What are the effects of pancreatic insufficiency?

Answer 2

Maldigestion
Malabsorption
Diarrhoea
Steatorrhoea
Weight loss
Malnutrition
Deficiency of fat soluble vitamins (A,D,E & K)
Diabetes

Question 3

How would someone present with chronic pancreatitis?

Answer 3

Severe pain
Weight loss
Cachexia
Note: can be difficult to differentiate from carcinoma.

Question 4

How would you test for pancreatic damage? What would you expect?

Answer 4

Serum amylase, >3x normal suggests acute pancreatitis.

Note: elevation does NOT reflect severity.

Question 5

What is the reticuloendothelial system involved in?

Answer 5

The degradation of RBCs. It involves the liver and spleen.

Question 6

What is the first step in the degradation of haem?

Answer 6

Bilirubin formation.

Question 7

What is the serum tumour maker for pancreatic cancer?

Answer 7

CA19-9

Question 8

What are the survival rates for pancreatic cancer?

Answer 8

5 year survival is less than 5%

Question 9

What is the main organ involved in pancreatic secretion?

Answer 9

Duodenum

Question 10

What do endocrine cells release in the presence of duodenal acid?

Answer 10

Secretin

Question 11

What do pancreatic duct cells release into the duodenum?

Answer 11

Bicarbonate - neutralising it

Question 12

What are the stimulatory and inhibitory hormones of the pancreas?

Answer 12

Stimulatory - CCK and secretin. CCK stimulates pancreatic enzyme secretion (e.g. amylase), Secretin stimulates bicarbonate realase.

Inhibitory - Peptide YY and somatostatin. Both inhibit enzyme secretion

Question 13

What are the 3 cell types of the pancreatic gland? What do they secrete?

Answer 13

Duct cells - HCO3
Acinar cells - 80% of pancreas, synthesise and secrete pancreatic enzymes
Islet cells - Endocrine function - secrete insulin, glucagon, somatostatin, pancreatic peptide

Question 14

What pancreatic lipolytic enzymes attack lipid emulsion droplets?

Answer 14

Lipase, colipase, phospholipase A2, cholesterol esterase

Question 15

What is the difference between bile acids and bile salts?

Answer 15

Bile salts are conjugated with taurine or glycine

Question 16

What cells are responsible for removing bile salts and acids from the portal blood?

Answer 16

Parenchymal cells

Question 17

Why do bile acids need a carrier in the portal blood? What is it?

Answer 17

They are hydrophobic. Albumin carries them

Question 18

What enzyme catalyses the breakdown of heme?

Answer 18

Heme oxygenase

Question 19

What enzyme reduces biliverdin to form bilirubin?

Answer 19

Biliverdin reductase

Question 20

What drugs can displace bilirubin from albumin?

Answer 20

Sulfonamides and salycilates

Question 21

How is the solubility of bilirubin increased?

Answer 21

Addition of 2 molecules of glucaronic acid. Catalysed by bilirubin glucuronyltransferase

Question 23

What are most urobilinogens oxidised to?

Answer 23

Intestinal bacteria oxidise most to stercobilin. This gives stool its characteristic brown colour

Question 24

Where are RBCs mainly degraded?

Answer 24

In the liver and spleen

Question 25

Describe the production of bilirubin

Answer 25

• Heme is degraded -> heme oxygenase catalyses this. It is broken down into biliverdin
• Biliverdin is reduced by biliverdin reductase to bilirubin

Question 26

What colour is the pigment biliverdin?

Answer 26

Green

Question 27

What colour is bilirubin?

Answer 27

Red-orange

Question 28

What is the term for bilirubin and derivatives?

Answer 28

Bile pigments

Question 29

How is bilirubin transported to the liver?

Answer 29

By binding albumin

Question 30

When bilirubin dissocaites from albumin and enters hepatocytes, what does it bind to?

Answer 30

Intracellular proteins such as ligandin

Question 31

How is the solubility of bilirubin increased in the liver?

Answer 31

It is bound to 2 molecules of glucuronic acid by bilirubin glucuronyltransferase.

Question 32

Where are urobilins formed?

Answer 32

In the intestine

Question 33

What is the first urobilin formed?

Answer 33

Urobilinogen

Question 34

What happens to a small amount of urobilinogen?

Answer 34

Some urobilinogen reabsorbed from gut -> portal blood -> kidneys where it is converted to urobilins and excreted. It is the colour of urine

Question 35

What happens to most of the urobilinogen?

Answer 35

They are oxidised by intestinal bacteria into stercobilin, which gives stool it’s brown colour

Question 36

What are the most common bile acids?

Answer 36

cholic acid and chenodeoxycholic acid

Question 37

Where does most lipid digestion take place?

Answer 37

In the duodenum

Question 38

What 2 things happen after/due to CCK release?

Answer 38

Gall bladder contraction and secretin release

Question 39

What is the term for pancreatic digestive enzymes?

Answer 39

Zymogens

Question 40

What happens to form mixed micelles from emulsion drolplets?

Answer 40

Addition of bile salts and lipase

Question 41

What does cholic acid conjugate with to become a bile salt? Name the salt produced

Answer 41

Glycine. Forms glycocholic acid

Question 42

What does chenodeoxycholic acid conjugate with to form a bile salt? Name the salt

Answer 42

Taurine. Taurochenodeoxycholic acid

Question 43

Chenodeoxycholic acid is a primary bile acid, what is the secondary bile acid it forms from the removal of the OH group?

Answer 43

Lithocholic acid

Question 44

What is the name of the secondary bile acid formed form cholic acid?

Answer 44

Deoxycholic acid