TABLE 1.

Hill model dose-response fit parameters ± S.E. for ENaC channels in native tracheal epithelia of WT, L/L, and βENaC-Tg mice

Parameters were obtained from averaged amiloride dose-response data (see Fig. 6, C and D) fitted with single and two-component Hill equations (see “Experimental Procedures”). Results are consistent with tracheal tissues from βENaC-Tg mice expressing a subpopulation of ENaC channels with low affinity toward amiloride. NS, not significantly different.

	Single component Hill model IC50	Two-component Hill model			Statistical comparison single versus two-component modela
		High affinity IC50	High affinity relative population Ifrct	Low affinity IC50
	μm	μm	%	μm
WT	0.3 ± 0.0	0.3 ± 0.2	86 ± 105	0.9 ± 4.4	NS
L/L	0.6 ± 0.0	0.2 ± 0.2	22 ± 31	0.8 ± 0.3	NS
βENaC-Tg	1.8 ± 0.4	0.6 ± 0.1	64 ± 3.2	30.9 ± 0.7	p < 0.025

^a βENaC-Tg F_calc(3, 7) = 59.3; WT F_calc(3, 5) = 0.2; Liddle F_calc(3, 5) = 2.5.