8.1 Pancreas Structure and Function

Question 1

Which mesothelial structure attaches to the anterior surface of the pancreas?

Answer 1

Transverse mesocolon

Question 2

Which two blood vessels travel in the gap created by the uncus of the pancreas?

Answer 2

Superior mesenteric a. and v.

Question 3

List the three ligaments that connect the spleen to surrounding anatomical structures

Answer 3

1. Gastrosplenic ligament
2. Splenorenal ligament
3. Pancreaticosplenic ligament

(Think of it like three lines converging to a point at the spleen; one from pancreas, one from stomach, one from kidney)

Question 4

Which peritoneal space does the pancreas sit in? Which is the only entry/exit point to that space, and why does this matter?

Answer 4

• Lesser sac of peritoneum
• Only point of communication is the foramen of Winslow; this enables fluid to build up quite easily

Question 5

The foramen of Winslow is posterior to…

Answer 5

The portal triad

Question 6

Describe the three main arteries (and their branches) that supply the pancreas

Answer 6

1. Splenic artery (short branches, dorsal branches, transverse branches)
2. Hepatic artery (gastroduodenal branch gives off pancreaticoduodenal, which supplies the pancreas)
3. Superior mesenteric artery (why does this make sense?)

Question 7

Which veins drain the pancreas?

Answer 7

• Splenic and superior mesenteric vein
• Therefore, all drains into hepatic portal vein (why does this make sense?)

Question 8

Which nodes does the pancreas drain into locally? How did this affect Steve Jobs?

Answer 8

• Drain into superior pancreatic, hepatic, celiac, superior mesenteric, and splenic nodes
• This allows for easy metastatic spread of cancers, such as in the case of Steve Jobs

Question 9

Describe the innervation of the pancreas (hint: what section(s) of the nervous system innervate it?)

Answer 9

• Purely autonomic innervation; both para and sympa
• Parasympa via vagus nerve
• Sympa via superior mesenteric and celiac plexuses

Question 10

What are the two main pancreatic ducts? Which is superior/inferior?

Answer 10

Superior: Accessory pancreatic duct
Inferior: Main pancreatic duct

Question 11

Via what ampulla/sphincter do pancreatic secretions drain into the duodenum? What else enter the GI tract there?

Answer 11

• Ampulla of vater/sphincter of Oddi
• Bile is also released here

Question 12

How are pancreatic proteases activated?

Answer 12

• Enterokinase activates trypsinogen into trypsin
• Trypsin activates chymotripsinogen/procarboxypeptidase

(Enterokinase enters the equation, and trypsin acts as a trypwire)

Question 13

Which types of pancreatic enzymes are secreted in their active/inactive forms? Why is this possible?

Answer 13

• Proteases are released in inactive form, since they would otherwise digest cellular proteins within the pancreas
• Lipases and amylases are released in their active form, since there are no triglycerides or polysaccharides that play a structural role in the pancreas