Pancreas Liver And Gallbladder

Question 1

What mechanism reduces the hypertonicity of chyme?

Answer 1

Movement of water from ECF into the duodenum

This makes chyme isotonic by when it leaves the duodenum

Question 2

What part of the pancreas produces enzymes?

What is it stimulated by?

Answer 2

Acinus

Stimulated by vagus nerve and cholecystokinin

Question 3

Why must proteases be secreted as zymogens into the duodenum?

Answer 3

To avoid auto digestion of the pancreas and pancreatic duct

Question 4

What do active pancreatic enzymes such as lipase and amylase in the bloodstream indicate?

Answer 4

Pancreatic damage or pathology

Question 5

Where is secretin secreted from?

What does it do?

Answer 5

S cells of duodenum in response to low pH.

Neutralises acidic chyme

Question 6

Which blood vessels supply the majority of blood to the liver?

Answer 6

Hepatic portal vein branches (80%)

Majority of liver blood flow is deoxygenated

Question 7

What makes up a hepatic portal triad?

Answer 7

Portal vein, hepatic artery and bile duct

Question 8

Outline the system of venous drainage for a hepatic portal triad

Answer 8

Portal veins - central veins - hepatic veins - IVC

Question 9

Which zone of a liver acinus is most likely to be damaged by ischaemia?
Which zone is most likely damaged by toxicity?

Answer 9

Zone 3.

Zone 1.

Question 10

Where do bile and pancreatic secretions drain through to reach the duodenum?

Answer 10

Ampulla of Vater and sphincter of Oddi

Question 11

What is the bile acid dependant component of bile?

What is the bile acid independent component?

Answer 11

Bile acids and pigments secreted by the hepatocytes.

Alkaline secretion secreted by duct cells stimulated by secretin.

Question 12

What 2 primary bile acids make up bile?

What are bile salts?

Answer 12

Cholic acid,
Chenodeoxycholic acid
Bile salts are bile acids conjugated by the amino acids glycine and taurine.

Question 13

Why are bile salts better than bile acids?

Answer 13

Bile salts are active at duodenal pHs

Bile salts have an amphipathic structure that allows them to emulsify lipids

Question 14

What is the function of micelles?

Answer 14

Vehicles to carry hydrophobic lipid molecules through aqueous medium and diffuse across brush borders of epithelial cells

Question 15

What happen to the products of lipid digestion in the basal epithelial cells of intestines?

Answer 15

Reesterified into triglycerides phospholipids and cholesterol and packaged into chylomicrons

Question 16

What is the path of chylomicrons around the body starting at intestinal epithelial cells?

Answer 16

Exocytosis from cells - enter lacteals (lymphatic capillaries) - travel through lymphatic system - enter vascular circulation at thoracic duct.

Question 17

What effect does fibre have on bile salts?

Answer 17

Binds to them and facilitates their excretion in faeces, forcing the liver to produce more and as such reducing plasma cholesterol levels

Question 18

What is the function of the gallbladder?

Answer 18

Store and concentrate bile produced by the liver,

Release bile when stimulated by CCK causing contraction

Question 19

What is steatorrhoea?

Answer 19

Lipids in faeces

Pale appearance and foul smell

Question 20

What risk factors are there for gallstones?

Answer 20

Obesity,
Age >40,
Rapid weight loss,
Caucasian descent,
Female.

Question 21

What causes pigmented gallstones?

What risk factors are there for these?

Answer 21

Bilirubin in the gallbladder.

Haemolysis.

Question 22

What is Biliary colic?

What characterises this?

Answer 22

Gallstones lodged in cystic duct,
RUQ pain radiating to shoulder tip after meals
Lasts 30 mins to 8 hours
Nausea and vomiting

Question 23

What characterises acute cholecysitis?

Answer 23

Nausea and vomiting,
Constant RUQ pain and tenderness radiating to shoulder tip
Fever.

Question 24

What characterises Ascending Cholangitis?

Answer 24

Charcots triad - (RUQ pain and tenderness, jaundice, fever)
Nausea and vomiting
Dark urine and pale stools

Question 25

What is reynolds pentad?

Answer 25

Symptoms of Ascending Cholangitis - Jaundice, RUQ pain and tenderness, fever, hypotension and confusion.

Question 26

What bloods investigations should be done for gallstones?

Answer 26

FBC, LFT, UE, amylase (indicates pancreatitis) and blood cultures

Question 27

If acute cholecystitis is suspected, what investigations can be done?

Answer 27

MRCP and ERCP (ERCP also used to treat gallstones lodged in cystic or bile ducts.

Question 28

What management is considered after removing gallstones?

Answer 28

Cholecystectomy