Pancreatic Secretion Flashcards
What neutralizes most of the gastric acid secretions
HCO3 (aqueous portion)
What cells secrete the aqueous portion of pancreatic secretions
Ductal cells
Major stimulant of ductal cells
Secretin
What cells secrete the pancreatic enzymes
Acinar cells
Major stimulants for acinar cells
CCK and Ach
Where are the granules located in the acinar cells
Basal membrane (unlike stomach)
How does CCK activate acinar cells
Initiates vagal-vagal reflexes (no CCK receptors in pancreas)
Where does almost all of the pancreatic HCO3 come from
blood
What channel does secretin act in ductal cells
Luminal Cl channels
What ions increase as pancreatic flow goes up? down?
HCO3 increases
Cl goes down
Two pancreatic enzymes that are secreted in active form?
Amylase and Lipase
What goes up in cephalic phase of pancreatic secretion?
Only pancreatic enzymes goes up (all via vagus nerve)
Only tiny increases in volume and bicarb
What gets activated in cephalic phase
Vagus gets Ach to activate acinar cells
When is secretin released?
When duodenal pH drops below 4.5
What does secretin effect?
Ductal cells
Ach also works to potentiate ductal cell activation
two things involved in pancreatic secretion potentiation for bicarb release
Secretin and phenylalanine
