Table 1.

Reversal potential (E_rev) and stoichiometry (n) of KNBC1 mutants (values for the corresponding EGFP-tagged constructs are in italics)

		DNDD		NNNN		DNNN		DNDN
Treatment	[Na+]AP/[Na+]BL	Erev	n	Erev	n	Erev	n	Erev	n
None	10/50	−20.1 ± 2 (6)	3.1 ± 0.3	−21.4 ± 2 (4)	3.0 ± 0.3	−22.9 ± 2 (4)	2.8 ± 0.3	−21.2 ± 2 (4)	3.0 ± 0.3
		−19.4 ± 2 (4)	3.2 ± 0.3	−20.8 ± 2 (5)	3.0 ± 0.3	−23.5 ± 2 (5)	2.8 ± 0.3
	50/10	23.2 ± 2 (5)	2.8 ± 0.3	19.9 ± 2 (4)	3.1 ± 0.3	23.2 ± 2 (4)	2.8 ± 0.3	19.7 ± 2 (6)	3.1 ± 0.3
		21.5 ± 2 (4)	2.9 ± 0.3	20.2 ± 2 (4)	3.1 ± 0.3	23.7 ± 2 (4)	2.8 ± 0.3
8-Br-cAMP	10/50	−38.2 ± 4 (7)*	2.1 ± 0.2*	−22.5 ± 2 (6)	2.9 ± 0.3	−21.6 ± 2 (4)	2.9 ± 0.3	−36.2 ± 4 (5)	2.1 ± 0.2*
		−37.6 ± 4 (6)*	2.1 ± 0.2*	−22.2 ± 2 (4)	2.9 ± 0.3	−20.9 ± 2 (4)	3.0 ± 0.3
	50/10	37.5 ± 4 (8)*	2.1 ± 0.2*	19.8 ± 2 (4)	3.1 ± 03	24.4 ± 2 (4)	2.7 ± 0.3	34.7 ± 4 (4)	22 ± 0.2*
		44.2 ± 4 (5)*	1.9 ± 0.2*	23.2 ± 2 (5)	2.8 ± 0.3	23.3 ± 2 (3)	2.8 ± 0.3
ACTZ	50/10	−25.0 ± 2 (3)	2.7 ± 0.2
8-Br-cAMP + ACTZ	50/10	−39.8 ± 4 (3)*	2.1 ± 0.2*

		DNND		NNDD		S989D		S982D/DNND
Treatment	[Na+]AP/[Na+]BL	Erev	n	Erev	n	Erev	n	Erev	n
None	10/50	−22.5 ± 2 (6)	2.9 ± 0.3	−23.2 ± 2 (4)	2.8 ± 0.3	−39.2 ± 4 (5)	2.1 ± 0.2*	−22.5 ± 2 (6)	2.9 ± 0.3
	50/10	21.7 ± 2 (7)	2.9 ± 0.3	24.6 ± 2 (4)	2.7 ± 0.3	41.0 ± 2 (4)	2.0 ± 0.2*	21.7 ± 2 (7)	2.9 ± 0.3
8-Br-cAMP	10/50	−20.8 ± 2 (4)	3.0 ± 0.3	−22.8 ± 2 (3)	2.8 ± 0.3	−38.9 ± 4 (4)	2.1 ± 0.2*	−20.8 ± 2 (4)	3.0 ± 0.3
	50/10	18.7 ± 2 (5)	3.2 ± 0.3	23.4 ± 2 (3)	2.8 ± 0.3	37.7 ± 4 (3)	2.1 ± 0.2*	18.7 ± 2 (5)	3.2 ± 0.3

[Na⁺]_AP/[Na⁺]_BL, apical/basolateral sodium gradient. Number of experiments is shown in parentheses.

^*P < 0.05 compared with the corresponding wt-KNBC1 construct in untreated cells; ACTZ, acetazolamide.