Figure 2. Functional analysis of CFTR and Ca²⁺-activated Cl⁻ channels in Cftr^+/+ and Cftr^−/− mice smooth muscle cells.

The stimulation of iodide efflux as a function of time was evoked in solution containing 80 mm K⁺ by 100 nm angiotensin II (denoted AgII) and 1 μm isoproterenol (A), and cAMP agonists (10 μm forskolin, 500 μm IBMX and 500 μm cpt-cAMP) and 300 nm VIP (B) in Cftr^+/+ (left) and Cftr^−/− (right) mice as compared to basal. C, summary of the relative rates presented as means ±s.e.m.D, effect of 100 μm glibenclamide, 500 μm DPC and 100 nm calixarene on the efflux stimulated by 300 nm VIP or cAMP agonists in Cftr^+/+ mouse smooth muscle cells as indicated. Basal was vehicle alone. Data are presented as means ±s.e.m. All experimental conditions have been repeated: n = 8. ***P < 0.001. ns: non-significant difference.