Using what you have learned about epithelial transport, draw a picture of the salivary duct cells and lumen.
Arrange the following membrane channels and transporters on the apical and basolateral membranes so that the duct cell absorbs Na+ and secretes K+:
ENaC, Na+-K+-ATPase, and K+ leak channel.
With neural stimulation, the flow rate of saliva can increase from 0.4 mL/min to 2 mL/min.
What do you think happens to the Na+ and K+ content of saliva at the higher flow rate?