Table 5.

Model predictions at macula densa under normal- and low-salt conditions

Conditions	Normal	Low Salt	Low Salt	Low Salt	Low Salt	Low Salt
NKCC2 Isoform	Base Case	Base Case	Switch	Base Case	Switch	Switch
Na+-K+-ATPase	Base Case	Base Case	Base Case	+50%	+50%	Segment Specific*
Lumen [Na+]	44.3	37.8	36.4	35.8	35.1	34.5
Lumen [Cl−]	33.5	24.0	21.0	20.2	17.7	17.9
Lumen [K+]	2.66	3.13	3.50	3.11	3.42	3.36
Lumen [NH4+]	1.66	1.78	1.14	1.86	1.26	1.27
Vbl	−82.7	−86.8	−88.3	−88.6	−90.7	−90.9
NHE Na+ flux	105	93.1	105	92.8	113	114
NKCC2 Na+ flux	21.5	−1.66	−11.4	−3.44	−11.7	−11.3
NKCC2 K+ flux	−72.1	−74.8	−103	−67.0	−104	−105
NKCC2 NH+4 flux	93.7	73.2	91.8	63.6	92.0	93.5

^*See text.