Development, Gross Anatomy and Functional Histology of the Pancreas Flashcards
What are the structures of the digestive tract? (5)
Oral cavity
Esophagus
Stomach
Small and large intestine
Rectum and anus
What is the purpose of the associated glands?
Help with the digestion process
What are examples of the associated glands?
Salivary glands
Liver
Pancreas
What are the different types of salary glands found?
Submandibular
Parotid
Sublingual
What are the functions of the salivary glands?
They wet and lubricate
Initiate the digestion
Secrete germicidal protective substances
Synthesis of blood proteins
What are the functions of the liver?
Produces bile
Metabolism and inactivation
Synthesis of blood proteins
What are examples of blood proteins produced by the liver?
Albumin, transferin etc
What are the functions of the pancreas?
Produces digestive enzymes
Secretes hormones (endocrine function)
What is the function of the gallbladder?
Stores & concentrates bile
What is the boundary between the foregut and the midgut?
The opening of the small bile duct
Where does the pancreas develop from?
It is an outgrowth of endoderm near the distal end of the foregut
What influences the development of the pancreas?
The fibroblast growth factors from the cardiac mesoderm
Which structures of the pancreas are derived from the dorsal mesentery?
The dorsal pancreatic bud
Which structures of the pancreas are derived from the ventral mesentery?
Ventral pancreatic bud
Liver
Gallbladder
What does the ventral pancreatic bud end up becoming?
Uncinate process
What happens to the ventral pancreatic bud during the rotation?
During the rotation it will approach the dorsal pancreatic bud and eventually merge to form the pancreas
What happens to the dorsal pancreatic bud during the rotation?
Nothing, it remains fixed in place since it is attached to the dorsal mesentery
When does the mesoderm septum transversum thin out and why?
As the proliferating endoderm cells that will form the liver tissue extend into the septum transversum
What is the mesoderm of the septum transversum eventually reduced to?
Hepatic sinusoids and stroma
Capsule of the liver
Lesser omentum
The falciform, triangular and coronary ligaments
Where do the dorsal and ventral ducts merge together?
Near the opening of the common bile duct
Which structures form the main pancreatic duct?
The distal part of the dorsal pancreatic bud and the whole of the vernal pancreatic bud
What happens to the proximal part of the dorsal pancreatic bud?
It either disappears or it becomes the accessory pancreatic duct
Where does the accessory pancreatic duct drain?
Minor duodenal papilla
What happens if the proximal part of the dorsal pancreatic bud just disappears and does not develop into the accessory duct?
There are no consequences, the accessory pancreatic duct is just an alternative and extra part of the duct system.
What is the sphincter of Oddi and where is it found?
It is the smooth muscle around the major duodenal papilla
Which duct drains into the major duodenal papilla?
Common bile duct and main pancreatic duct
What kind of structure is the pancreas? (intraperitoneal, retroperitoneal or sub peritoneal)
Secondary retroperitoneal, because initially part of it was attached to the mesentery and then during the rotation it detached
What are the variation in union of bile and pancreatic ducts? Explain them
Short common channel, both of them join together through the same channel
No common channel, they enter as separate structures
Long common channel, the pancreatic duct attaches to the common bile duct and they then enter through the same channel
Which mesocolon structure is anterior to the pancreas?
Transverse mesocolon
What is an annular pancreas?
A rare condition in which the second part of the duodenum is surrounded by a ring of pancreatic tissue continuous with the head of the pancreas
How does an annular pancreas occur?
Part of the pancreas will rotate to one side, whilst the other part will rotate from the other side
What is the main complication of an annular pancreas?
The portion of the pancreas that has rotated in the wrong direction can constrict the duodenum and block or impair the flow of blood to the rest of the intestines
What are the different parts of the pancreas?
Head
Neck
Body
Tail
Where is the splenic artery located in regards to the parts of the pancreas? What is its characteristic feature?
The splenic artery is located above the head and it is identified by the spiral character of it
Where is the pancreas located?
Within the c-loop of the duodenum
What is the pancreas surrounded by?
Thin fibrous connective tissue
What does the connective tissue septa divide the pancreas into?
Lobules
Which structure is the tail of the pancreas attached to?
Attached to the hilum of the spleen
Which blood vessels form the portal vein?
The superior mesenteric and the splenic artery
Where is the portal vein located?
Behind the neck of the pancreas
What is the Uncinate process? How do you differentiate it?
It has the same functional cells as the rest of the pancreas; part of the pancreas. Derived from the ventral pancreatic bud.
The superior mesenteric trunk is anterior to it
Where is the superior mesentery trunk located?
Anterior to the 3rd part of the duodenum and Uncinate process
What ligament / pancreatic reflection may the tail of pancreas run along?
The splenorenal ligament, splenic artery also reaches the hilum from the same ligament
What are the blood vessels anteriorly and posteriorly to the uncinate process and the 3rd part of the duodenum?
Superior mesenteric vessels anteriorly
Aorta and portal vein posteriorly
Which artery is the pancreatic artery a branch of?
The splenic artery
Where are the anterior and posterior SUPERIOR pancreaticoduodenal arteries derived from?
Branches of the gastroduodenal
Where are the anterior and posterior INFERIOR pancreaticoduodenal arteries derived from?
Branches of the superior mesenteric artery
What are the veins of the pancreas like?
The veins correspond to the arteries and flow into the portal vein
Where is the lymph from the body and tail of the pancreas emptied?
The pancreaticosplenic lymph nodes which are located along the splenic artery, emptied via the lymphatic vessels
Where do the vessels of the head of the pancreas empty their lymph?
Pyloric lymph nodes
Where is the lymph then transported to?
Superior mesenteric lymph nodes and celiac lymph nodes
What are the components of the pancreas?
Exocrine and endocrine
What is the pancreas covered by?
A thin capsule of connective tissue
What do the connective tissue septa house and how is that significant?
It houses capillary networks, it is significant in tumor metastases