Physiology and Pathology: The Pancreas Flashcards
Four parts of the pancreas?
- Head and uncinate process
- Neck
- Body
- Tail
________ joins ________ at the hepatopancreatic ampulla (ampulla of vater)
Main pancreatic duct joins the common bile duct
Accessory pancreatic duct drains to what?
The minor duodenal papilla
Is the pancreas a retro-peritoneal structure?
yes
Arterial supply of pancreas head?
- Pancreaticoduodenal branches of the gastroduodenal artery
- Superior mesenteric artery
Arterial supply of pancreas neck, body, tail?
- Branches of splenic artery (celiac trunk)
Venous supply of the pancreas?
- Splenic vein
- Superior mesenteric vein
The exocrine functions of the pancreas are carried out by what?
The acini
What type of gland system is the exocrine pancreas?
Compound tubulo-acinar
The compound tubulo-acinar gland system produces ______ rich fluid containing digestive enzymes
Bicarbonate
Acinar cells surround _______ cells - which function to line what?
Centro-acinar cells - line the lumen of the acinus = beginning of intercalated ducts
Intercalated ducts branch from the lumen of the acinus and merge into what?
Interlobular ducts
General functions of acinar cells? (3)
- Secretion of inactive pancreatic enzymes (zymogens)
- Rich RER, lots of granules
- CCK major stimulator
General function of centroacinar cells? (2)
- Secretion of bicarb-rich fluid
- Secretin major stimulator
What two cell types secrete bicarbonate in response to secretin?
- Centro-acinar cells
- Intercalated duct cells
_____ diffuses from blood in to cell to combine with water to form ______
CO2 + H2O => Carbonic acid
Carbonic acid dissociates to form what?
HCO3- and H+
HCO3- is actively transported into the duct and what follows?
Na+
Movement of HCO3- and Na+ into the ducts creates what? Causes what?
Osmotic pressure causing osmosis of H2O into duct
Three phases of pancreatic secretion?
- Cephalic
- Gastric
- Intestinal
Cephalic phase stimulants?
Sight, smell, taste, mastication
Cephalic regulatory pathway?
Vagal pathway
Percentage of maximum enzyme secretion of cephalic phase?
20%
Gastric phase stimulants?
Distention, Gastrin (?)
Cephalic regulatory pathway?
Vagal-cholinergic pathway
Percentage of maximum enzyme secretion of gastric phase?
10-20%
Intestinal phase stimulants?
Amino acids, FAs, H+ (after chyme leaves stomach)
Intestinal regulatory pathway?
CCK and Secretin (most), Enteropancreatic reflexes
Percentage of maximum enzyme secretion of intestinal phase?
50-80%
Regulation of pancreatic secretetion has both ______ and ______ control
Neural and hormonal
What phases are mostly regulated through nervous system?
Cephalic and gastric phases
What phase is mostly under hormonal control?
Intestinal phase
What is the source of secretin and what is its stimulus?
Source = S cells lining duodenum
Stim = Acid entering duodenum