salivary secretion Flashcards
acini- at rest describe the k+ and na+ ions
inside=k high
outside=na high
acini- when activated what happens 1st?
increased permeability to K+- k+ flows into secretion/lumen and into extracellular matrix
acini- what happens 2nd?
increased k+ in extracellular matrix- activates basal na, k and cl co-transporter - all 3 flow into cell
acini-what happens 3rd?
there is increase in na/k exchange- results in no na increase
and k and cl flow into lumen/secretion
acini-what happens when na and cl flow into secretion/lumen? and what happens to overcome this and what is the result?
causes a shift in charge- so na flows between cells leading to osmotic imbalance
acini -what happens when there is an osmotic imbalance within the secretion?
h20 flows between cells = isotonic solution
acini-where does the secretion go to next and then after?
the intercalated duct to the striated duct unchanged
SD- what is impermeable to SD cells at rest?
h2o
SD- is the concentration of cl- higher inside or outside the cell at rest?
outside
what is the isotonic solution from acini changed to in the SD?
hypotonic
SD-when activated, what happens first?
na and k pump increases activity- potential decrease in na and increase in k
SD- what happens 2nd?
due to reduction in na and increase in k within cell there is compensatory movements of na from secretion into cell and k from cell into secretion
SD- what happens as the na moves from the secretion into the cell?
cl moves from the secretion to the cell too
SD-what kind of transport is the compensatory transporter?
passive
SD-what is the 3rd thing to happen?
there is an active transport of hco3 into secretion and cl into cell
are acini affected by flow rate?
no, but the na k pump will work harder
how does low flow rate affect SD?
-lots of time for na resorption- low levels of na in saliva
how does high flow rate affect SD?
little time for na resorption- high levels in secretion
how does low flow rate affect secretion in sd?
less k
how does high flow rate affects secretion in SD?
higher k, cl and hco3
where are the organic proteins made?
in the acini
how are the organic proteins made in the acini?
proteins made from ribosomes of RER using mitochondria for atp- then exocytosed
what does the parasympathetic nerves release?
REST AND DIGEST
serous saliva
high volume
vasodilation
what does the sympathetic nerves release?
FIGHT OR FLIGHT
thick sticky saliva
low volume
vasoconstriction