Hepatic, Biliary and Pancreatic anatomy

Question 1

Abdominal cavity

Answer 1

Right lobe of liver, left lobe of liver, under the liver is the gall bladder, spleen stomach and pancreas
Pancreas is a retroperitoneal organ, pancreatitis pain radiates to the back

Liver starts at the 5th intercostal space , 15 x 15, 1.8 kg for M, 1.5 kg for f

Question 2

biliary tree

Answer 2

bile canaliculi empty into the right and left hepatic duct, empty into the common hepatic duct, the common hepatic duct and the cystic duct join to make the common bile duct

Question 3

blood supply to accessory organs

Answer 3

Portal vein goes into the liver, hepatic artery (off of celiac trunk), Portal vein brings in 2/3rds of blood to liver other 1/3 is via the hepatic artery

Portal triad: Portal v, proper hepatic A, common bile duct

Major duodenal papilla surrounds the sphincter of Odi, drainage for common bile and common bile ducts

Hepatic vein drains the liver, divides the liver in 8 segments

Liver cancers fed by hepatic artery

Question 4

Liver ligaments

Answer 4

Falciform ligament attaches the liver to the anterior body wall
Coronary ligament attaches the liver to the diaphragm superiorly
Round ligament- obliterated umbilical vein

Question 5

Pancreas

Answer 5

drains in the major papilla
head of pancreas blocks the bile duct, tail doesnt block anything

Head is close to the vascular structures,

Question 6

Hepatic histology

Answer 6

hepatic lobule is a 6 sided structure, in the middle is a central vein

each corner of a lobule gets a vein from the portal vein, an artery from the hepatic artery

the central veins converge to form the hepatic vein

the branches of the hepatic artery and portal vein drain in the sinusoids to the central vein, all liver damage (cirrhosis, cancer etc) occurs in the sinusoids

Question 7

Sinusoids

Answer 7

have fenestrations along the walls that allow the draining blood to go thru them and into the space of disse. On the other side of the space of disse is the hepatocyte wall. So it would be: from in to out, sinusoid, festration, space of disse, hepatocytes (Which make proteins, albumin clotting factors)
Space between hepatocytes empty into bile duct
Hepatocytes also make bile which drain in the opposite direction from central vein to lobule edge into bile duct

sinusoids contain Kupffer cells (makes TNF-a and inflammation when exposed to toxic substances)

In space of disse is a stelate cell (ITO)- makes collagen when expozed to toxins like alcohol- obliterates space of dise

Question 8

Hepatic acinus

Answer 8

2 central veins are connected which are connected to 2 portal triads making a diamond

Each half diamond is broken up into segment 1 2 and 3

Segment 1- closest to blood supply, sees more viral products, drug toxicity
Segment 3- furthest from blood supply (more susceptible to ischemic blood injury)

Question 9

Gallbladder versus liver bile

Answer 9

Volume goes from 500 mls to 50 ml, absorption of water, sodium, and chloride leads to concentration of bile salts, cholesterol and bilirubin

cholesterol solubilized by bile salts

bile acids are reabsorbed in the ilium 90%

Question 10

Bile salt function

Answer 10

emulsification: decreases surface tension and breaks fat glocules into smaller sized particles

Forms micells- soluble in chyme and helps absorption of fat breakdown products, fatty acids, monoglycerides and cholesterol

Question 11

Effects of CCK and secretin

Answer 11

CCK/ cholecystokinin- fatty foods in the duodenum results in release of CCK–> gallbladder contraction and emptying in under 1 hour (acetylcholine from the vagus can also do this but to a lesser degree), CCK also causes relaxation of sphincter of odi

Secretin: acts on biliary epithelium to produce a solution rich in sodium bicarbonate to neutralize acid and optimize pancreatic function

Question 12

Pancreatic structure

Answer 12

pancreatic secretions in response to chyme in upper small intestine with juice characteristics depndent on type of fuid

make digestive enzymes and bicarbonate rich solutions

CCK-Acini secrete digestive enzymes (lipase-fats, amylase- carbs, Trypsin-proteins),
Secretin- ducts secrete bicarb to neutralize pH

Question 13

Proteins digestion

Answer 13

trypsin, chymotrypsin and carboxypolypeptidase

Secreted in inactive form (Chymotrypsin, chymotrypsinogen, and procarboxypolypeptidase)

Trypsinogen gets avtivated by enterokinase (in small intestine- if activated in pancreas, will start digesting the pancreas)

Trypsin further activates trypsinogen, chymotripsinogen and procarboxypeptidase

Trypsin inhibitor in the pancrease prevents activation in pancreas

Question 14

bicarb secretion

Answer 14

H20 and CO2 from blood diffuse in the ductal cells, Carbonic anhydrase converts them into H2CO2–> H+ and HCO3 (bicarb),

H is exchanged for Na and Sodium / Bicarb leave into the lumen