Table 2.

The effects of ENaC blocker compounds on the guinea-pig tracheal potential difference

Compound	ED50 (μg kg−1; i.t.)	Dose (μg kg−1; i.t.)	TPD (mV)	n
Amiloride	16	0	−10.5±1.1	10
		3.0	−9.8±1.2	6
		30	−6.0±0.4a	8
		300	−4.4±0.2a	4
		3000	−4.3±0.4a	4
Benzamil	14	0	−8.8±0.5	20
		1.0	−10.1±1.4	7
		10	−6.0±0.4	5
		100	−4.3±0.6a	6
		1000	−3.0±0.5a	6
		10 000	−2.9±0.9a	6
CF552	0.2	0	−10.5±1.0	9
		0.01	−9.8±0.9	4
		0.1	−7.8±0.9	4
		1.0	−7.1±0.4b	4
		10	−5.1±0.3a	4
		100	−5.2±0.4a	6
EIPA	>300	0	−9.7±1.3	5
		300	−10.0±0.6	5

Mean absolute tracheal potential difference values±s.e.mean obtained in groups of guinea-pigs dosed with either vehicle (0.2 mL 5% dextrose) or test compound by i.t. instillation. One-way ANOVA followed by Dunnett's multiple comparison test was used to test for differences between compound-treated and vehicle control groups.

^aP<0.01.

^bP<0.05.

EIPA was tested up to the limit of solubility in 5% dextrose.