Chloride channels conductance

CFTR has a single-channel conductance of about 8 pS. It is present in the apical membranes of many epithelia. Its mutation leads to the potentially lethal disease cystic fibrosis. In addition to acting as a chloride channel, CFTR is also thought to regulate, e.g., the epithelial sodium channel ENaC, a molecularly unknown outwardly-rectifying chloride channel, and possibly also potassium channels and water channels. Some of these potential regulatory processes, however, are controversial. CFTR also acts as a receptor for bacteria. 

Hardy SP, Valverde MA (1994) Novel plasma membrane action of estrogen and antiestrogens revealed by their regulation of a large conductance chloride channel. FASEB J 8(10) 760-765... 

CFTR (cystic fibrosis transmembrane conductance regulator) a membrane protein that functions as a chloride channel. 

The gene responsible for CF codes for the cystic fibrosis transmembrane conductance regulator (CFTR), which is a chloride channel expressed on the surface of epithelial cells that line the affected organs. 

The cystic fibrosis (c/) gene was first identified in 1989. It codes for a 170 kDa protein, the cystic fibrosis transmembrane conductance regulator (CFTR), which serves as a chloride channel in epithelial cells. Inheritance of a mutant cftr gene from both parents results in the CF phenotype. While various organs are affected, the most severely affected are the respiratory epithelial cells, which have, unsurprisingly, become the focus of attempts at corrective gene therapy. 

Another suggested mechanism of action involves the chloride channel. As discussed previously, the chloride channel is intimately associated with neuronal inhibition, and its activity appears to be modulated at many different sites. Caffeine can compete for binding at the benzodiazepine site and would therefore be expected to reduce chloride conductance. Thus, caffeine may act functionally like the analeptic stimulants that limit chloride channel activation. 

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