TABLE 1.
Intracellular pH, [H+], [HCO3−] and Nernst equilibrium potential of H+/HCO3− in oocytes expressing either MCT1, NBC, MCT1+NBC or one (H2O-injected) in salines buffered with 5 mM HEPES or in the presence of added 5% CO2/10 mM HCO3− at pH 7.0
| MCT1 (1) (n = 7) | NBC (2) (n = 8) | MCT1 + NBC (3) (n = 16) | H2O-(4) (n = 7) injected (Control) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Oocyte injected with cRNA for | ||||||||||||
| pHi | HEPES | 7.33 ± 0.05 | *** | 2 − | 7.34 ± 0.05 | *** | 3 − | 7.46 ± 0.04 | *** | 4 ** | 7.25 ± 0.03 | *** |
| 3 − | 4 − | |||||||||||
| 4 − | ||||||||||||
| CO2 | 6.91 ± 0.05 | 2 * | 7.07 ± 0.05 | 3 − | 7.09 ± 0.03 | 4 *** | 6.79 ± 0.03 | |||||
| 3 ** | 4 *** | |||||||||||
| 4 − | ||||||||||||
| [H+]i (nM) | HEPES | 49 ± 5 | *** | 2 − | 48 ± 6 | *** | 3 − | 38 ± 4 | *** | 4 * | 57 ± 4 | *** |
| 3 − | 4 − | |||||||||||
| 4 − | ||||||||||||
| 2 * | 3 − | 86 ± 6 | 4 *** | 163 ± 9 | ||||||||
| CO2 | 128 ± 14 | 3 * | 89 ± 11 | 4 *** | ||||||||
| 4 − | ||||||||||||
| [HCO3−]i (mM) | HEPES | 0.14 ± 0.02 | *** | 2 − | *** | 3 − | 0.19 ± 0.02 | *** | 4 *** | 0.11 ± 0.01 | *** | |
| 3 − | 0.14 ± 0.02 | 4 − | ||||||||||
| 4 − | ||||||||||||
| 2 * | 3 − | 12.5 ± 0.8 | 4 *** | 4 *** | 6.2 ± 0.3 | |||||||
| CO2 | 8.3 ± 0.9 | 3 ** | 12.2 ± 1.2 | 4 *** | ||||||||
| 4 − | ||||||||||||
| EH+/HCO3− (mV) | HEPES | 19 ± 3 | *** | 2 − | 20 ± 3 | *** | 3 − | 27 ± 2 | *** | 4 ** | 15 ± 2 | *** |
| 3 − | ||||||||||||
| 4 − | 4 − | |||||||||||
| CO2 | −5 ± 3 | 2 * | 4 ± 3 | 3 − | 5 ± 2 | 4 *** | −12 ± 1 | |||||
| 4 *** | ||||||||||||
Asterisks indicate significance level to column numbered 1–4