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    Can someone explain to me how chloride is transported through cells in people with cystic fibrosis?

    From my understanding, the channel that transports chloride is blocked or doesn't function properly - therefore there is a net movement of water into cells - causing problems in the lungs, pancreas and sweat glands. But if chloride can't be transported, how is it absorbed and manage to reach these organs in the first place?
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    there are many, many different forms of ion channels. my understanding is that one is affected, so chloride flow is reduced, causing mucus to thicken as water leaves the mucus on the epithelium, and enters the cells via osmosis (as there are far too many Cl- ions there).

    however, Cl- are transported in the blood, and can still move by diffusion, and active transport using other channels, so overall chloride flow in the body as a whole is unlikely to be affected.
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    (Original post by sea tea)
    there are many, many different forms of ion channels. my understanding is that one is affected, so chloride flow is reduced, causing mucus to thicken as water leaves the mucus on the epithelium, and enters the cells via osmosis (as there are far too many Cl- ions there).

    however, Cl- are transported in the blood, and can still move by diffusion, and active transport using other channels, so overall chloride flow in the body as a whole is unlikely to be affected.
    so Cl- are only transported via the cftr channel in the lungs/pancreas/liver/etc and they are transported in/out of other cells via different channel(s) in all other parts of the body?
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    I'm pretty sure the CFTR is only found in the cells that line the lungs, digestive tract and sweat glands. There are other channels which transport the ions across other membranes.
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    Thanks. I understand it better now. Am I on the right track with this:
    http://www.cf.ac.uk/biosi/staff/jaco.../ionchan2.html ?
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    From my lecturer's digestion book, I deduced thatthe CFTR channel transports Cl- out of cells into the lumen (eg of the pancreatic duct). If this channel is faulty, there is no build up a Cl- gradient, as normally Cl- would exchange into the cell for HCO3- out of the cell. So it results in a lack of HCO3- in the lumen which causes proteins to concentrate and plug, blocking the ducts.
 
 
 
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