Normal Physiology: Effects of normal total CFTR activity
The CFTR gene is expressed in epithelial tissue of multiple organs throughout the body. The cystic fibrosis transmembrane conductance regulator, or CFTR, channel plays an important role in maintaining electrolytes and fluid balance in many organ systems. The regulated transport of electrolytes and fluid is necessary for the proper function of the airway, pancreas, gastrointestinal tract, and sweat glands, among others. In individuals without CF, normal expression of CFTR protein and normal CFTR activity contribute to the proper function of these organs.1-5
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CFTR proteins help regulate salt and water balance, which contributes to normal mucus hydration and clearance from the sinonasal passages
CFTR proteins regulate transport of chloride and bicarbonate to maintain a normal volume and pH of pancreatic secretions necessary for digestion of nutrients
CFTR-regulated balance of electrolytes and fluid allows for normal hydration and appropriate intestinal pH, as well as normal composition of intestinal secretions
In the sweat duct, chloride passes through the CFTR channels following sodium absorption, to maintain normal sweat chloride levels
CFTR proteins help regulate salt and water balance, which contributes to normal hydration of airways and normal mucociliary clearance
CFTR regulation of chloride and bicarbonate transport helps foster normal development of vas deferens in males; CFTR-regulated salt and water balance helps to hydrate cervical mucus in females
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- Welsh MJ, Ramsey BW, Accurso F, Cutting GR. Cystic fibrosis: membrane transport disorders. In: Valle D, Beaudet A, Vogelstein B, et al, eds. The Online Metabolic & Molecular Bases of Inherited Disease. The McGraw‐Hill Companies Inc; 2004:part 21, chap 201. www.ommbid.com.
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