Pancreas Flashcards
What are the 5 parts of the pancreas?
Tail, body, neck, head, uncinate process
What is the arterial supply to the body and tail of the pancreas?
Pancreatic branches of the splenic artery
What is the arterial supply to the head, neck and body of the pancreas?
Superior pancreaticoduodenal artery from the gastroduodenal
What is the arterial supply to the head and uncinate process of the pancreas?
Inferior pancreaticoduodenal artery from superior mesenteric
What is the venous drainage from the body, neck and tail of the pancreas?
Splenic vein
What is the venous drainage from the head and uncinate process of the pancreas?
Superior mesenteric vein
At what week does insulin secretion begin?
Week 20
What parts of the pancreas does the dorsal bud give rise to?
Part of the head, neck, body and tail
What parts of the pancreas does the ventral bud give rise to?
Part of the head and the uncinaste process
What do PP cells secrete?
Pancreatic polypeptide
What do alpha cells secrete?
Glucagon
What do beta cells secrete?
Insulin
What do delta cells secrete?
Somatostatin
What are the exocrine secretions of the pancreas?
HCO3-, Zymogens, Digestive enzymes
What is the role of HCO3-?
Neutralises chyme in the duodenum
What stimulates HCO3- release?
Secretin
What are the roles of zymogens?
Exist to protect pancreatic cells from autodigestion
What is the key enzyme in activating zymogens?
Enterokinase
What digestive enzymes are released by the pancreas?
Pancreatic lipase, trypsin, alpha amylase
What inhibits the release of digestive enzymes?
Somatostatin
What stimulates the release of digestive enzymes?
CCK
What percentage of islet cells are alpha cells?
20%
What percentage of islet cells are beta cells?
75%
What percentage of islet cells are delta cells?
4%
By what transporter does glucose normally enter the cell?
GLUT-2
What does excess ATP within the cell cause?
Closing of the kATP channel, causing depolarisation, thus opening of the voltage gated Ca2+ channels
What does an influx of Ca2+ in the cell cause?
Activation of insulin gene expression via CREB, and exocytosis of stored insulin
What does binding of insulin to the insulin receptor cause within the cell?
Translocation of GLUT4, cell growth, protein synthesis, glycogen synthesis, glucose transport
What is the average blood glucose levels?
About 99 mg/100ml
