Table 2.
Analysis of Na+ and K+ and of the ENaC-mediated Na+ reabsorption
| +/+ | +/− | −/− | |
|---|---|---|---|
| Measurement | |||
| 1. Plasma Na+, mmol/l | 141.1 ± 3.2 | 143.6 ± 2.0 | 132.8 ± 2.2* |
| (n = 15) | (n = 17) | (n = 13) | |
| 2. Plasma K+, mmol/l | 6.3 ± 0.3 | 6.3 ± 0.3 | 8.1 ± 0.5* |
| (n = 14) | (n = 15) | (n = 11) | |
| 3. Urine Na+, mmol/l | 9.1 ± 1.2 | 19.6 ± 2.5** | 35.4 ± 3.3** |
| (n = 19) | (n = 19) | (n = 14) | |
| 4. Urine K+, mmol/l | 83.7 ± 3.4 | 81.1 ± 5.3 | 71.9 ± 4.8 |
| (n = 18) | (n = 19) | (n = 14) | |
| 5. Fractional excretion of Na+, % | 0.33 ± 0.07 | 0.93 ± 0.15** | 2.74 ± 0.61** |
| (n = 13) | (n = 12) | (n = 9) | |
| 6. Fractional excretion of K+, % | 89.8 ± 15.8 | 80.9 ± 8.9 | 98.2 ± 15.4 |
| (n = 13) | (n = 12) | (n = 9) | |
| 7. Glomerular filtration rate, μl/min⋅g | 1.27 ± 0.16 | 1.12 ± 0.13 | 1.01 ± 0.29 |
| (n = 15) | (n = 24) | (n = 9) | |
| 8. Fractional excretion of Na+ after amiloride injection, % | 7.95 ± 1.27 | 8.47 ± 0.96 | 4.54 ± 0.54* |
| (n = 10) | (n = 13) | (n = 8) | |
| 9. Colonic amiloride inhibitable transepithelial voltage, Δ mV | 11.3 ± 0.9 | 10.8 ± 1.5 | 1.8 ± 0.4** |
| (n = 14) | (n = 8) | (n = 13) |
All measurements were performed on 8-day-old mice. Results shown are mean ± SEM.
Values of MR-deficient (−/−) or heterozygous (+/−) animals that are statistically different from wild-type animals (+/+) are marked with asterisks.
*
P < 0.05 (Student’s t test, unpaired).
**
P < 0.005 (Student’s t test, unpaired).