9. Exocrine Pancreas Flashcards
What are the names of the two sets of lymph nodes closest to the duodenum?
Anterior and posterior pancreaticoduodenal lymph nodes
What are the two embryological buds that the pancreas develops from?
Dorsal and ventral
What are the endocrine cells of the pancreas? And what do each of them secrete?
Alpha - glucagon
Beta - insulin
Delta - somatostatin
PP - pancreatic polypeptide
What are the exocrine cells of the pancreas? And what do they secrete?
Acinar - produce enzymes
Duct - secrete bicarbonate/water
Centroacinar - stem cell
What form are the enzymes that acinar cells secrete?
Inactive zygotes
Where are enzymes released from?
Zymogen granules
What regulates teh release of enzymes?
Cholecytokinin -> it’s activation triggers release
How does tripsinogen become tripsin?
Tripsinogen is digested by enerokinase which cuts off the inhibitory part of the protein allowing active tripsin to be produced
What does the binding of secretin on ductal cells cause?
Binding causes release of CAMP - causes release of chloride
Chloride then exchanged for bicarbonate
The release of bicarbonate
What happens in chronic pancreatitis?
Build up of fibrosis
Loss of muscle masss
Almost inevitably fatal
What happens in pancreatic cancer?
Epithelium of the duct is thickened, inflammation of fibrosis
Patient loses muscle mass
Almost inevitable fatal
What is acute pancreatitis caused by?
Necrosis [cell death with inflammation]
Early - Systemic inflammatory response SIRS
Late - multi organ dysfunction syndrome
Death
Endocrine failure
Exocrine failure - malabsorption
Cancer
What is the pathogenesis of pancreatitis in acinar cells?
Tripsinogen activated
Active tripsin within acinar cells
Causes cell damage
Causes cytokine release
Leads to necrosis and pancreatitis
What activates tripsinogen in acinar cells?
Not too sure
But peaks in Ca2+
I GET SMASHED
Eteology of pancreatitis
Idiopathic - dont know cause
Gallstones - main cause
Ethanol
Trauma
Steroids
Mumps
Autoimmune
Scorpion stings
Hyper - calcaemia, lipidaemia ,thermia
Ercp
Drugs
What is the supposed relationship between gallstones and pancreatitis?
Gallstones get stuck and block bile release
What autosomal recessive disease can lead to pancreatitis?
Cystic fibrosis
How does continued alcohol abuse cause chronic pancreatitis?
Continued alcohol abuse - continues acute attacks of pancreatitis - eventually leads to fibrosis and chronic pancreatitis
Why does alcohol cause pancreatitis?
Alcohol metabolised 2 ways - oxidative and non oxidative
Oxidative- acetate - no calcium spike - pancreatitis
Non oxidative - fatty acid ethyl esters - calcium spike - pancreatitis
How does calcium release cause tripsin to be activated in acinar cells?
Calcium released due to trigger
Fuses lysosomes with zymogen granules
Lysosomes contain proteases which activate tripsinogen
