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* to cd45 or anyone..
  saan - 11/23/06 16:56
  can u pls explain the CFTR FUNCTION in cystic fibrosis.

it causes reabsorption of Cl n Na from swaet gland.

in bronchioles it causes cl secretion.

pls expain it ,i got confused.
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* Re:to cd45 or anyone..
  luckyalways - 11/23/06 17:50
  The CFTR gene provides instructions for making a protein called the cystic fibrosis

transmembrane conductance regulator. This protein functions as a channel across the

membrane of cells that produce mucus, sweat, saliva, tears, and digestive enzymes. The

channel transports negatively charged particles called chloride ions into and out of cells. The

transport of chloride ions helps control the movement of water in tissues and maintain the

fluidity of mucus and other secretions. Mucus is a slippery substance that lubricates and

protects the lining of the airways, digestive system, reproductive system, and other organs

and tissues.

The CFTR protein also regulates the function of other channels, such as those that transport positively charged particles called sodium ions across cell membranes. These channels are necessary for the normal function of organs such as the lungs and pancreas.

Disease-causing mutations in the CFTR gene alter the production, structure, or stability of the chloride channel. All of these changes prevent the channel from functioning properly, which impairs the transport of chloride ions and the movement of water into and out of cells. As a result, cells that line the passageways of the lungs, pancreas, and other organs produce mucus that is abnormally thick and sticky. The abnormal mucus obstructs the airways and glands, leading to the characteristic signs and symptoms of cystic fibrosis
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* Re:to cd45 or anyone..
  saan - 11/23/06 18:06
  thanks lucyalways.  
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* Re:to cd45 or anyone..
  cd45 - 11/24/06 00:09
  sorry saan i was sleeping
luckyalways has written it too technically for me to even try to read it.
hmmm just remem that somehow god knows why action of the CFTR is diff in the sweat glands that in the rest of the glands

in the sweat glands mutation of CFTR causes impaired CL reabsorption and impaired Na reabsoprtion..positive sweat test

In the other glands mutation of CFTR causes impaired Cl secretion and increased Na and H2O reabsortion.. drying the mucus
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* Re:to cd45 or anyone..
  saan - 11/24/06 08:48
  hey cd45 many thanks.u explained it in a simple way .i have same concept but i got cofused by a it is cleared.thanks .goodluck to all of u.  
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