TABLE 1.

The effect of dietary Na⁺ on ENaC activity in BK-β4^−/− mice

	% Dietary Na+	NPo	N	Po	f a
Wild type	<0.01	1.4 ± 0.18	2.9 ± 0.30	0.45 ± 0.03	0.46 (42/93)
	0.32	0.79 ± 0.18b	2.4 ± 0.31	0.26 ± 0.03b	0.46 (36/79)
	2.0	0.35 ± 0.09b	1.6 ± 0.18b	0.16 ± 0.03b	0.32 (29/88)
BK-β4−/−	<0.01	2.0 ± 0.47	4.5 ± 0.81c	0.43 ± 0.05	0.50 (10/20)
	0.32	1.0 ± 0.13b	2.6 ± 0.25b	0.40 ± 0.03c	0.50 (36/72)
	2.0	1.2 ± 0.23b,c	3.3 ± 0.53c	0.33 ± 0.04c	0.47 (14/30)

^a f = frequency (patches with at least one active channel/total number of viable seals for that condition).

^b Significant decrease vs. <0.01 Na⁺.

^c Significantly greater compared to wild type under identical conditions.