FIGURE 4.
ENaC in BK-β4 null mice retains sensitivity to exogenous ATP. A, shown is a representative gap-free current trace for ENaC from a BK-β4 null mouse before (1) and after 10 μm ATP (2) and then 100 μm suramin plus 10 units/ml hexokinase and 5 mm glucose (3). Holding potential is −60 mV. The closed state is noted with dashed lines and c. B, shown are areas before (1) and after (2) ATP and suramin plus hexokinase (3) shown at expanded time scales. C, shown is a summary graph of ENaC Po before and after ATP and suramin (Sur) plus hexokinase (Hexo). *, significantly less than before. **, significantly greater compared with ATP.