Figure 2

Effect of CFTR mutation heterozygosity on smoke-induced CFTR dysfunction in vivo . C57BL/6 J mice expressing wild type CFTR (CFTR +/+) or heterozygous CFTR (CFTR +/-) were exposed to whole cigarette smoke (4 cigarettes, twice daily) or room air control in whole body chambers for 2 weeks prior to CFTR functional estimation with nasal potential difference (NPD). A) Representative tracings of NPD measured in CFTR +/+ or CFTR +/- mice exposed to either cigarette smoke or air control. Initiation of amiloride (100 μM), Cl^- free ringers and Cl^- free ringers plus forskolin (20 μM) are indicated. B) Mean forskolin stimulated change in nasal potential difference, an indicator of CFTR mediated cl^- transport. N = 8/condition, *P < 0.05, **P < 0.005.