Loss of CFTR Chloride Channels Alters Salt Absorption by Cystic Fibrosis Airway Epithelia In Vitro
1998; Elsevier BV; Volume: 2; Issue: 3 Linguagem: Inglês
10.1016/s1097-2765(00)80284-1
ISSN1097-4164
AutoresJoseph Zabner, Jeffrey J. Smith, Philip H. Karp, J. H. Widdicombe, Michael J. Welsh,
Tópico(s)Neonatal Respiratory Health Research
ResumoCystic fibrosis (CF) is caused by the loss of functional CFTR Cl− channels. However, it is not understood how this defect disrupts salt and liquid movement in the airway or whether it alters the NaCl concentration in the thin liquid film covering the airway surface. Using a new approach, we found that CF airway surface liquid had a higher NaCl concentration than normal. Both CF and non-CF epithelia absorbed salt and liquid; however, expression of CFTR Cl− channels was required for maximal absorption. Thus, loss of CFTR elevates the salt concentration in CF airway surface liquid and in sweat by related mechanisms; the elevated NaCl concentration is due to a block in transcellular Cl− movement. The high NaCl may predispose CF airways to bacterial infections by inhibiting endogenous antibacterial defenses.
Referência(s)