Table 3.
1:1-per-ATP model |
2:2-per-ATP model |
|||
---|---|---|---|---|
C50, mM | R2 | C50, mM | R2 | |
Experiment 1 (K+ concentration varies) | 0.240 ± 0.000 | 1.00 | 0.228 ± 0.000 | 1.00 |
Experiment 2 (NH4+ concentration varies) | 0.915 ± 0.003 | 0.996 | 0.807 ± 0.005 | 1.00 |
Experiment 3 (Na+ concentration varies; NH4+-free bath) | 3.25 ± 0.00 | 0.999 | 4.25 ± 0.01 | 0.993 |
Experiment 4 (Na+ concentration varies, K+-free bath) | 2.66 ± 0.01 | 0.974 | 4.12 ± 0.01 | 0.991 |
C50, half-maximal ion concentration. Each data set (i.e., lines that fit circles and squares in Fig. 2, A and B for the 1:1 model and C and D for 2:2 model) was fitted using Eq. 38 [Hill coefficient (n) = 1 for the 1:1 model and n = 2 for the 2:2 model] to obtain C50 (see Normalization methods in the appendix).